mirror of
git://git.musl-libc.org/musl
synced 2024-12-27 09:12:10 +00:00
833a469167
unlike most projects that use -fno-strict-aliasing, we aim to have all sources respect the C language rules for effective type that make type-based alias analysis optimizations possible. unfortunately, it turns out that there are deep, and likely very difficult to fix, flaws in the TBAA performed by GCC and likely other compilers, whereby this kind of optimization can transform code that follows the rules strictly in ways that will make it malfunction. see for example GCC bugs 107107 and 107115, the latter of which also affects clang. there are not presently any known instances of breakage due to wrong type-based aliasing optimizations in our codebase. nonetheless, since the transformations are unsound and could introduce breakage, configure CFLAGS to build with -fno-strict-aliasing. some casual analysis of the effects on codegen suggest that this is unlikely to affect performance except possibly in the regex engine. in general, we should probably prefer making better use of the restrict keyword over relying on types to imply non-aliasing for optimization purposes; doing so should be able to get back any performance that was lost and more, should it turn out to matter (unlikely).
816 lines
25 KiB
Bash
Executable File
816 lines
25 KiB
Bash
Executable File
#!/bin/sh
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usage () {
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cat <<EOF
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Usage: $0 [OPTION]... [VAR=VALUE]... [TARGET]
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To assign environment variables (e.g., CC, CFLAGS...), specify them as
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VAR=VALUE. See below for descriptions of some of the useful variables.
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Defaults for the options are specified in brackets.
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Configuration:
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--srcdir=DIR source directory [detected]
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Installation directories:
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--prefix=PREFIX main installation prefix [/usr/local/musl]
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--exec-prefix=EPREFIX installation prefix for executable files [PREFIX]
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Fine tuning of the installation directories:
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--bindir=DIR user executables [EPREFIX/bin]
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--libdir=DIR library files for the linker [PREFIX/lib]
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--includedir=DIR include files for the C compiler [PREFIX/include]
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--syslibdir=DIR location for the dynamic linker [/lib]
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System types:
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--target=TARGET configure to run on target TARGET [detected]
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--host=HOST same as --target
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--build=BUILD build system type; used only to infer cross-compiling
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Optional features:
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--enable-optimize=... optimize listed components for speed over size [auto]
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--enable-debug build with debugging information [disabled]
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--disable-warnings build with recommended warnings flags [enabled]
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--enable-wrapper=... build given musl toolchain wrapper [auto]
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--disable-shared inhibit building shared library [enabled]
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--disable-static inhibit building static library [enabled]
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Optional packages:
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--with-malloc=... choose malloc implementation [mallocng]
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Some influential environment variables:
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CC C compiler command [detected]
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CFLAGS C compiler flags [-Os -pipe ...]
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CROSS_COMPILE prefix for cross compiler and tools [none]
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LIBCC compiler runtime library [detected]
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Use these variables to override the choices made by configure.
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EOF
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exit 0
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}
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# Helper functions
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quote () {
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tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
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$1
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EOF
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printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
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}
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echo () { printf "%s\n" "$*" ; }
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fail () { echo "$*" ; exit 1 ; }
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fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
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cmdexists () { type "$1" >/dev/null 2>&1 ; }
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trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
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stripdir () {
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while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
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}
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trycppif () {
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printf "checking preprocessor condition %s... " "$1"
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echo "typedef int x;" > "$tmpc"
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echo "#if $1" >> "$tmpc"
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echo "#error yes" >> "$tmpc"
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echo "#endif" >> "$tmpc"
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if $CC $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
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printf "false\n"
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return 1
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else
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printf "true\n"
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return 0
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fi
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}
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tryflag () {
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printf "checking whether compiler accepts %s... " "$2"
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echo "typedef int x;" > "$tmpc"
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if $CC $CFLAGS_TRY $2 -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
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printf "yes\n"
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eval "$1=\"\${$1} \$2\""
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eval "$1=\${$1# }"
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return 0
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else
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printf "no\n"
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return 1
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fi
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}
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tryldflag () {
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printf "checking whether linker accepts %s... " "$2"
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echo "typedef int x;" > "$tmpc"
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if $CC $LDFLAGS_TRY -nostdlib -shared "$2" -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
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printf "yes\n"
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eval "$1=\"\${$1} \$2\""
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eval "$1=\${$1# }"
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return 0
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else
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printf "no\n"
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return 1
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fi
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}
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# Beginning of actual script
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CFLAGS_C99FSE=
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CFLAGS_AUTO=
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CFLAGS_MEMOPS=
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CFLAGS_NOSSP=
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CFLAGS_TRY=
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LDFLAGS_AUTO=
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LDFLAGS_TRY=
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OPTIMIZE_GLOBS=
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srcdir=
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prefix=/usr/local/musl
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exec_prefix='$(prefix)'
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bindir='$(exec_prefix)/bin'
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libdir='$(prefix)/lib'
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includedir='$(prefix)/include'
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syslibdir='/lib'
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tools=
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tool_libs=
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build=
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target=
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optimize=auto
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debug=no
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warnings=yes
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shared=auto
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static=yes
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wrapper=auto
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gcc_wrapper=no
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clang_wrapper=no
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malloc_dir=mallocng
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for arg ; do
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case "$arg" in
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--help|-h) usage ;;
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--srcdir=*) srcdir=${arg#*=} ;;
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--prefix=*) prefix=${arg#*=} ;;
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--exec-prefix=*) exec_prefix=${arg#*=} ;;
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--bindir=*) bindir=${arg#*=} ;;
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--libdir=*) libdir=${arg#*=} ;;
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--includedir=*) includedir=${arg#*=} ;;
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--syslibdir=*) syslibdir=${arg#*=} ;;
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--enable-shared|--enable-shared=yes) shared=yes ;;
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--disable-shared|--enable-shared=no) shared=no ;;
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--enable-static|--enable-static=yes) static=yes ;;
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--disable-static|--enable-static=no) static=no ;;
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--enable-optimize) optimize=yes ;;
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--enable-optimize=*) optimize=${arg#*=} ;;
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--disable-optimize) optimize=no ;;
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--enable-debug|--enable-debug=yes) debug=yes ;;
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--disable-debug|--enable-debug=no) debug=no ;;
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--enable-warnings|--enable-warnings=yes) warnings=yes ;;
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--disable-warnings|--enable-warnings=no) warnings=no ;;
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--enable-wrapper|--enable-wrapper=yes) wrapper=detect ;;
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--enable-wrapper=all) wrapper=yes ; gcc_wrapper=yes ; clang_wrapper=yes ;;
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--enable-wrapper=gcc) wrapper=yes ; gcc_wrapper=yes ;;
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--enable-wrapper=clang) wrapper=yes ; clang_wrapper=yes ;;
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--disable-wrapper|--enable-wrapper=no) wrapper=no ;;
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--enable-gcc-wrapper|--enable-gcc-wrapper=yes) wrapper=yes ; gcc_wrapper=yes ;;
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--disable-gcc-wrapper|--enable-gcc-wrapper=no) wrapper=no ;;
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--with-malloc=*) malloc_dir=${arg#*=} ;;
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--enable-*|--disable-*|--with-*|--without-*|--*dir=*) ;;
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--host=*|--target=*) target=${arg#*=} ;;
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--build=*) build=${arg#*=} ;;
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-* ) echo "$0: unknown option $arg" ;;
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AR=*) AR=${arg#*=} ;;
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RANLIB=*) RANLIB=${arg#*=} ;;
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CC=*) CC=${arg#*=} ;;
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CFLAGS=*) CFLAGS=${arg#*=} ;;
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CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
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LDFLAGS=*) LDFLAGS=${arg#*=} ;;
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CROSS_COMPILE=*) CROSS_COMPILE=${arg#*=} ;;
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LIBCC=*) LIBCC=${arg#*=} ;;
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*=*) ;;
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*) build=$arg ; target=$arg ;;
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esac
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done
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for i in srcdir prefix exec_prefix bindir libdir includedir syslibdir ; do
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stripdir $i
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done
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#
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# Get the source dir for out-of-tree builds
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#
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if test -z "$srcdir" ; then
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srcdir="${0%/configure}"
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stripdir srcdir
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fi
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abs_builddir="$(pwd)" || fail "$0: cannot determine working directory"
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abs_srcdir="$(cd $srcdir && pwd)" || fail "$0: invalid source directory $srcdir"
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test "$abs_srcdir" = "$abs_builddir" && srcdir=.
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test "$srcdir" != "." && test -f Makefile && test ! -h Makefile && fail "$0: Makefile already exists in the working directory"
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#
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# Get a temp filename we can use
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#
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i=0
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set -C
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while : ; do i=$(($i+1))
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tmpc="./conf$$-$PPID-$i.c"
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2>|/dev/null > "$tmpc" && break
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test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
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done
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set +C
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trap 'rm "$tmpc"' EXIT INT QUIT TERM HUP
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#
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# Check that the requested malloc implementation exists
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#
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test -d "$srcdir/src/malloc/$malloc_dir" \
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|| fail "$0: error: chosen malloc implementation '$malloc_dir' does not exist"
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#
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# Check whether we are cross-compiling, and set a default
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# CROSS_COMPILE prefix if none was provided.
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#
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test "$target" && \
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test "$target" != "$build" && \
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test -z "$CROSS_COMPILE" && \
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CROSS_COMPILE="$target-"
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#
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# Find a C compiler to use
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#
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printf "checking for C compiler... "
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trycc ${CROSS_COMPILE}gcc
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trycc ${CROSS_COMPILE}c99
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trycc ${CROSS_COMPILE}cc
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printf "%s\n" "$CC"
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test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
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printf "checking whether C compiler works... "
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echo "typedef int x;" > "$tmpc"
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if output=$($CC $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" 2>&1) ; then
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printf "yes\n"
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else
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printf "no; compiler output follows:\n%s\n" "$output"
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exit 1
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fi
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#
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# Figure out options to force errors on unknown flags.
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#
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tryflag CFLAGS_TRY -Werror=unknown-warning-option
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tryflag CFLAGS_TRY -Werror=unused-command-line-argument
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tryflag CFLAGS_TRY -Werror=ignored-optimization-argument
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tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
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tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
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#
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# Need to know if the compiler is gcc or clang to decide which toolchain
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# wrappers to build.
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#
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printf "checking for C compiler family... "
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cc_ver="$(LC_ALL=C $CC -v 2>&1)"
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cc_family=unknown
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if fnmatch '*gcc\ version*' "$cc_ver" ; then
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cc_family=gcc
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elif fnmatch '*clang\ version*' "$cc_ver" ; then
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cc_family=clang
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fi
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echo "$cc_family"
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#
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# Figure out toolchain wrapper to build
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#
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if test "$wrapper" = auto || test "$wrapper" = detect ; then
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echo "#include <stdlib.h>" > "$tmpc"
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echo "#if ! __GLIBC__" >> "$tmpc"
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echo "#error no" >> "$tmpc"
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echo "#endif" >> "$tmpc"
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printf "checking for toolchain wrapper to build... "
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if test "$wrapper" = auto && ! $CC -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
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echo "none"
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elif test "$cc_family" = gcc ; then
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gcc_wrapper=yes
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echo "gcc"
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elif test "$cc_family" = clang ; then
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clang_wrapper=yes
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echo "clang"
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else
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echo "none"
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if test "$wrapper" = detect ; then
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fail "$0: could not find an appropriate toolchain wrapper"
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fi
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fi
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fi
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if test "$gcc_wrapper" = yes ; then
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tools="$tools obj/musl-gcc"
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tool_libs="$tool_libs lib/musl-gcc.specs"
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fi
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if test "$clang_wrapper" = yes ; then
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tools="$tools obj/musl-clang obj/ld.musl-clang"
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fi
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#
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# Find the target architecture
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#
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printf "checking target system type... "
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test -n "$target" || target=$($CC -dumpmachine 2>/dev/null) || target=unknown
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printf "%s\n" "$target"
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#
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# Convert to just ARCH
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#
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case "$target" in
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# Catch these early to simplify matching for 32-bit archs
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arm*) ARCH=arm ;;
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aarch64*) ARCH=aarch64 ;;
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i?86-nt32*) ARCH=nt32 ;;
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i?86*) ARCH=i386 ;;
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x86_64-x32*|x32*|x86_64*x32) ARCH=x32 ;;
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x86_64-nt64*) ARCH=nt64 ;;
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x86_64*) ARCH=x86_64 ;;
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m68k*) ARCH=m68k ;;
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mips64*|mipsisa64*) ARCH=mips64 ;;
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mips*) ARCH=mips ;;
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microblaze*) ARCH=microblaze ;;
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or1k*) ARCH=or1k ;;
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powerpc64*|ppc64*) ARCH=powerpc64 ;;
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powerpc*|ppc*) ARCH=powerpc ;;
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riscv64*) ARCH=riscv64 ;;
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sh[1-9bel-]*|sh|superh*) ARCH=sh ;;
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s390x*) ARCH=s390x ;;
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unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;
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*) fail "$0: unknown or unsupported target \"$target\"" ;;
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esac
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#
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# Try to get a conforming C99 freestanding environment
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#
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tryflag CFLAGS_C99FSE -std=c99
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tryflag CFLAGS_C99FSE -nostdinc
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tryflag CFLAGS_C99FSE -ffreestanding \
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|| tryflag CFLAGS_C99FSE -fno-builtin
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tryflag CFLAGS_C99FSE -fexcess-precision=standard \
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|| { test "$ARCH" = i386 && tryflag CFLAGS_C99FSE -ffloat-store ; }
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tryflag CFLAGS_C99FSE -frounding-math
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#
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# Semantically we want to insist that our sources follow the
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# C rules for type-based aliasing, but most if not all real-world
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# compilers are known or suspected to have critical bugs in their
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# type-based aliasing analysis. See for example GCC bug 107107.
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#
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tryflag CFLAGS_C99FSE -fno-strict-aliasing
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#
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# We may use the may_alias attribute if __GNUC__ is defined, so
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# if the compiler defines __GNUC__ but does not provide it,
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# it must be defined away as part of the CFLAGS.
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#
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printf "checking whether compiler needs attribute((may_alias)) suppression... "
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cat > "$tmpc" <<EOF
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typedef int
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#ifdef __GNUC__
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__attribute__((__may_alias__))
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#endif
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x;
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EOF
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if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS \
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-c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
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printf "no\n"
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else
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printf "yes\n"
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CFLAGS_C99FSE="$CFLAGS_C99FSE -D__may_alias__="
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fi
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#
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# The GNU toolchain defaults to assuming unmarked files need an
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# executable stack, potentially exposing vulnerabilities in programs
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# linked with such object files. Fix this.
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#
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tryflag CFLAGS_C99FSE -Wa,--noexecstack
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#
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# Check for options to disable stack protector, which needs to be
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# disabled for a few early-bootstrap translation units. If not found,
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# this is not an error; we assume the toolchain does not do ssp.
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#
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tryflag CFLAGS_NOSSP -fno-stack-protector
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#
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# Check for options that may be needed to prevent the compiler from
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# generating self-referential versions of memcpy,, memmove, memcmp,
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# and memset. Really, we should add a check to determine if this
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# option is sufficient, and if not, add a macro to cripple these
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# functions with volatile...
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#
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tryflag CFLAGS_MEMOPS -fno-tree-loop-distribute-patterns
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#
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# Enable debugging if requessted.
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#
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test "$debug" = yes && CFLAGS_AUTO=-g
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#
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# Preprocess asm files to add extra debugging information if debug is
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# enabled, our assembler supports the needed directives, and the
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# preprocessing script has been written for our architecture.
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#
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printf "checking whether we should preprocess assembly to add debugging information... "
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if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" &&
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test -f "$srcdir/tools/add-cfi.$ARCH.awk" &&
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printf ".file 1 \"srcfile.s\"\n.line 1\n.cfi_startproc\n.cfi_endproc" | $CC -g -x assembler -c -o /dev/null 2>/dev/null -
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then
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ADD_CFI=yes
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else
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ADD_CFI=no
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fi
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printf "%s\n" "$ADD_CFI"
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#
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# Possibly add a -O option to CFLAGS and select modules to optimize with
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# -O3 based on the status of --enable-optimize and provided CFLAGS.
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#
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printf "checking for optimization settings... "
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case "x$optimize" in
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xauto)
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if fnmatch '-O*|*\ -O*' "$CFLAGS_AUTO $CFLAGS" ; then
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printf "using provided CFLAGS\n" ;optimize=no
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else
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printf "using defaults\n" ; optimize=yes
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fi
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;;
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xsize|xnone) printf "minimize size\n" ; optimize=size ;;
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xno|x) printf "disabled\n" ; optimize=no ;;
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*) printf "custom\n" ;;
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esac
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test "$optimize" = no || tryflag CFLAGS_AUTO -Os || tryflag CFLAGS_AUTO -O2
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test "$optimize" = yes && optimize="internal,malloc,string"
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if fnmatch 'no|size' "$optimize" ; then :
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else
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printf "components to be optimized for speed:"
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while test "$optimize" ; do
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case "$optimize" in
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*,*) this=${optimize%%,*} optimize=${optimize#*,} ;;
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*) this=$optimize optimize=
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esac
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printf " $this"
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case "$this" in
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*/*.c) ;;
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*/*) this=$this*.c ;;
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*) this=$this/*.c ;;
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esac
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OPTIMIZE_GLOBS="$OPTIMIZE_GLOBS $this"
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done
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OPTIMIZE_GLOBS=${OPTIMIZE_GLOBS# }
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printf "\n"
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fi
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# Always try -pipe
|
|
tryflag CFLAGS_AUTO -pipe
|
|
|
|
#
|
|
# If debugging is disabled, omit frame pointer. Modern GCC does this
|
|
# anyway on most archs even when debugging is enabled since the frame
|
|
# pointer is no longer needed for debugging.
|
|
#
|
|
if fnmatch '-g*|*\ -g*' "$CFLAGS_AUTO $CFLAGS" ; then :
|
|
else
|
|
tryflag CFLAGS_AUTO -fomit-frame-pointer
|
|
fi
|
|
|
|
#
|
|
# Modern GCC wants to put DWARF tables (used for debugging and
|
|
# unwinding) in the loaded part of the program where they are
|
|
# unstrippable. These options force them back to debug sections (and
|
|
# cause them not to get generated at all if debugging is off).
|
|
#
|
|
tryflag CFLAGS_AUTO -fno-unwind-tables
|
|
tryflag CFLAGS_AUTO -fno-asynchronous-unwind-tables
|
|
|
|
#
|
|
# Attempt to put each function and each data object in its own
|
|
# section. This both allows additional size optimizations at link
|
|
# time and works around a dangerous class of compiler/assembler bugs
|
|
# whereby relative address expressions are constant-folded by the
|
|
# assembler even when one or more of the symbols involved is
|
|
# replaceable. See gas pr 18561 and gcc pr 66609, 68178, etc.
|
|
#
|
|
tryflag CFLAGS_AUTO -ffunction-sections
|
|
tryflag CFLAGS_AUTO -fdata-sections
|
|
|
|
#
|
|
# On x86, make sure we don't have incompatible instruction set
|
|
# extensions enabled by default. This is bad for making static binaries.
|
|
# We cheat and use i486 rather than i386 because i386 really does not
|
|
# work anyway (issues with atomic ops).
|
|
# Some build environments pass -march and -mtune options via CC, so
|
|
# check both CC and CFLAGS.
|
|
#
|
|
if test "$ARCH" = "i386" ; then
|
|
fnmatch '-march=*|*\ -march=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -march=i486
|
|
fnmatch '-mtune=*|*\ -mtune=*' "$CC $CFLAGS" || tryldflag CFLAGS_AUTO -mtune=generic
|
|
fi
|
|
|
|
#
|
|
# GCC defines -w as overriding any -W options, regardless of order, but
|
|
# clang has a bunch of annoying warnings enabled by default and needs -w
|
|
# to start from a clean slate. So use -w if building with clang. Also
|
|
# turn off a common on-by-default cast warning regardless of compiler.
|
|
#
|
|
test "$cc_family" = clang && tryflag CFLAGS_AUTO -w
|
|
|
|
tryflag CFLAGS_AUTO -Wno-pointer-to-int-cast
|
|
|
|
#
|
|
# Even with -std=c99, gcc accepts some constructs which are constraint
|
|
# violations. We want to treat these as errors regardless of whether
|
|
# other purely stylistic warnings are enabled -- especially implicit
|
|
# function declarations, which are a dangerous programming error.
|
|
#
|
|
tryflag CFLAGS_AUTO -Werror=implicit-function-declaration
|
|
tryflag CFLAGS_AUTO -Werror=implicit-int
|
|
tryflag CFLAGS_AUTO -Werror=pointer-sign
|
|
tryflag CFLAGS_AUTO -Werror=pointer-arith
|
|
tryflag CFLAGS_AUTO -Werror=int-conversion
|
|
tryflag CFLAGS_AUTO -Werror=incompatible-pointer-types
|
|
tryflag CFLAGS_AUTO -Werror=discarded-qualifiers
|
|
tryflag CFLAGS_AUTO -Werror=discarded-array-qualifiers
|
|
|
|
#
|
|
# GCC ignores unused arguements by default, but Clang needs this extra
|
|
# parameter to stop printing warnings about LDFLAGS passed during
|
|
# compiling stage and CFLAGS passed during linking stage.
|
|
#
|
|
test "$cc_family" = clang && tryflag CFLAGS_AUTO -Qunused-arguments
|
|
|
|
if test "x$warnings" = xyes ; then
|
|
tryflag CFLAGS_AUTO -Waddress
|
|
tryflag CFLAGS_AUTO -Warray-bounds
|
|
tryflag CFLAGS_AUTO -Wchar-subscripts
|
|
tryflag CFLAGS_AUTO -Wduplicate-decl-specifier
|
|
tryflag CFLAGS_AUTO -Winit-self
|
|
tryflag CFLAGS_AUTO -Wreturn-type
|
|
tryflag CFLAGS_AUTO -Wsequence-point
|
|
tryflag CFLAGS_AUTO -Wstrict-aliasing
|
|
tryflag CFLAGS_AUTO -Wunused-function
|
|
tryflag CFLAGS_AUTO -Wunused-label
|
|
tryflag CFLAGS_AUTO -Wunused-variable
|
|
fi
|
|
|
|
# Determine if the compiler produces position-independent code (PIC)
|
|
# by default. If so, we don't need to compile separate object files
|
|
# for libc.a and libc.so.
|
|
if trycppif __PIC__ "$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
|
|
pic_default=yes
|
|
else
|
|
pic_default=no
|
|
fi
|
|
|
|
# Reduce space lost to padding for alignment purposes by sorting data
|
|
# objects according to their alignment reqirements. This approximates
|
|
# optimal packing.
|
|
tryldflag LDFLAGS_AUTO -Wl,--sort-section,alignment
|
|
tryldflag LDFLAGS_AUTO -Wl,--sort-common
|
|
|
|
# When linking shared library, drop dummy weak definitions that were
|
|
# replaced by strong definitions from other translation units.
|
|
tryldflag LDFLAGS_AUTO -Wl,--gc-sections
|
|
|
|
# Some patched GCC builds have these defaults messed up...
|
|
tryldflag LDFLAGS_AUTO -Wl,--hash-style=both
|
|
|
|
# Prevent linking if there are undefined symbols; if any exist,
|
|
# libc.so will crash at runtime during relocation processing.
|
|
# The common way this can happen is failure to link the compiler
|
|
# runtime library; implementation error is also a possibility.
|
|
tryldflag LDFLAGS_AUTO -Wl,--no-undefined
|
|
|
|
# Avoid exporting symbols from compiler runtime libraries. They
|
|
# should be hidden anyway, but some toolchains including old gcc
|
|
# versions built without shared library support and pcc are broken.
|
|
tryldflag LDFLAGS_AUTO -Wl,--exclude-libs=ALL
|
|
|
|
# Public data symbols must be interposable to allow for copy
|
|
# relocations, but otherwise we want to bind symbols at libc link
|
|
# time to eliminate startup relocations and PLT overhead. Use
|
|
# --dynamic-list rather than -Bsymbolic-functions for greater
|
|
# control over what symbols are left unbound.
|
|
tryldflag LDFLAGS_AUTO -Wl,--dynamic-list="$srcdir/dynamic.list"
|
|
|
|
# Find compiler runtime library
|
|
test -z "$LIBCC" && tryldflag LIBCC -lgcc && tryldflag LIBCC -lgcc_eh
|
|
test -z "$LIBCC" && tryldflag LIBCC -lcompiler_rt
|
|
test -z "$LIBCC" && try_libcc=`$CC -print-libgcc-file-name 2>/dev/null` \
|
|
&& tryldflag LIBCC "$try_libcc"
|
|
test -z "$LIBCC" && try_libcc=`$CC -print-file-name=libpcc.a 2>/dev/null` \
|
|
&& tryldflag LIBCC "$try_libcc"
|
|
printf "using compiler runtime libraries: %s\n" "$LIBCC"
|
|
|
|
# Figure out arch variants for archs with variants
|
|
SUBARCH=
|
|
t="$CFLAGS_C99FSE $CPPFLAGS $CFLAGS"
|
|
|
|
if test "$ARCH" = "i386" ; then
|
|
printf "checking whether compiler can use ebx in PIC asm constraints... "
|
|
cat > "$tmpc" <<EOF
|
|
int foo(int x) { __asm__ ( "" : "+b"(x) ); return x; }
|
|
EOF
|
|
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -fPIC \
|
|
-c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
|
|
printf "yes\n"
|
|
else
|
|
printf "no\n"
|
|
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_EBX_ASM"
|
|
fi
|
|
fi
|
|
|
|
if test "$ARCH" = "x86_64" ; then
|
|
trycppif __ILP32__ "$t" && ARCH=x32
|
|
fi
|
|
|
|
if test "$ARCH" = "arm" ; then
|
|
if trycppif __thumb2__ "$t" ; then
|
|
tryflag CFLAGS_AUTO -mimplicit-it=always
|
|
tryflag CFLAGS_AUTO -Wa,-mimplicit-it=always
|
|
tryflag CFLAGS_AUTO -Wa,-mthumb
|
|
fi
|
|
trycppif __ARMEB__ "$t" && SUBARCH=${SUBARCH}eb
|
|
trycppif __ARM_PCS_VFP "$t" && SUBARCH=${SUBARCH}hf
|
|
# Versions of clang up until at least 3.8 have the wrong constraint codes
|
|
# for floating point operands to inline asm. Detect this so the affected
|
|
# source files can just disable the asm.
|
|
if test "$cc_family" = clang ; then
|
|
printf "checking whether clang's vfp asm constraints work... "
|
|
echo 'float f(float x) { __asm__("":"+t"(x)); return x; }' > "$tmpc"
|
|
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
|
|
printf "yes\n"
|
|
else
|
|
printf "no\n"
|
|
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_VFP_ASM"
|
|
CFLAGS_AUTO="${CFLAGS_AUTO# }"
|
|
fi
|
|
fi
|
|
fi
|
|
|
|
if test "$ARCH" = "aarch64" ; then
|
|
trycppif __AARCH64EB__ "$t" && SUBARCH=${SUBARCH}_be
|
|
fi
|
|
|
|
if test "$ARCH" = "m68k" ; then
|
|
if trycppif "__HAVE_68881__" ; then : ;
|
|
elif trycppif "__mcffpu__" ; then SUBARCH="-fp64"
|
|
else SUBARCH="-sf"
|
|
fi
|
|
fi
|
|
|
|
if test "$ARCH" = "mips" ; then
|
|
trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
|
|
trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
|
|
trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
|
|
fi
|
|
|
|
if test "$ARCH" = "mips64" ; then
|
|
trycppif "_MIPS_SIM != _ABI64" "$t" && ARCH=mipsn32
|
|
trycppif "__mips_isa_rev >= 6" "$t" && SUBARCH=${SUBARCH}r6
|
|
trycppif "_MIPSEL || __MIPSEL || __MIPSEL__" "$t" && SUBARCH=${SUBARCH}el
|
|
trycppif __mips_soft_float "$t" && SUBARCH=${SUBARCH}-sf
|
|
fi
|
|
|
|
if test "$ARCH" = "powerpc" ; then
|
|
trycppif "_SOFT_FLOAT || __NO_FPRS__" "$t" && SUBARCH=${SUBARCH}-sf
|
|
printf "checking whether compiler can use 'd' constraint in asm... "
|
|
echo 'double f(double x) { __asm__ ("fabs %0, %1" : "=d"(x) : "d"(x)); return x; }' > "$tmpc"
|
|
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
|
|
printf "yes\n"
|
|
else
|
|
printf "no\n"
|
|
CFLAGS_AUTO="$CFLAGS_AUTO -DBROKEN_PPC_D_ASM"
|
|
CFLAGS_AUTO="${CFLAGS_AUTO# }"
|
|
fi
|
|
fi
|
|
|
|
test "$ARCH" = "microblaze" && trycppif __MICROBLAZEEL__ "$t" \
|
|
&& SUBARCH=${SUBARCH}el
|
|
|
|
if test "$ARCH" = "powerpc64" ; then
|
|
trycppif "_CALL_ELF == 2" "$t" || fail "$0: error: unsupported powerpc64 ABI"
|
|
trycppif __LITTLE_ENDIAN__ "$t" && SUBARCH=${SUBARCH}le
|
|
trycppif _SOFT_FLOAT "$t" && fail "$0: error: soft-float not supported on powerpc64"
|
|
fi
|
|
|
|
if test "$ARCH" = "riscv64" ; then
|
|
trycppif __riscv_float_abi_soft "$t" && SUBARCH=${SUBARCH}-sf
|
|
trycppif __riscv_float_abi_single "$t" && SUBARCH=${SUBARCH}-sp
|
|
fi
|
|
|
|
if test "$ARCH" = "sh" ; then
|
|
tryflag CFLAGS_AUTO -Wa,--isa=any
|
|
trycppif __BIG_ENDIAN__ "$t" && SUBARCH=${SUBARCH}eb
|
|
if trycppif "__SH_FPU_ANY__ || __SH4__" "$t" ; then
|
|
# Some sh configurations are broken and replace double with float
|
|
# rather than using softfloat when the fpu is present but only
|
|
# supports single precision. Reject them.
|
|
printf "checking whether compiler's double type is IEEE double... "
|
|
echo 'typedef char dblcheck[(int)sizeof(double)-5];' > "$tmpc"
|
|
if $CC $CFLAGS_C99FSE $CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
|
|
printf "yes\n"
|
|
else
|
|
printf "no\n"
|
|
fail "$0: error: compiler's floating point configuration is unsupported"
|
|
fi
|
|
else
|
|
SUBARCH=${SUBARCH}-nofpu
|
|
fi
|
|
if trycppif __SH_FDPIC__ "$t" ; then
|
|
SUBARCH=${SUBARCH}-fdpic
|
|
fi
|
|
fi
|
|
|
|
test "$SUBARCH" \
|
|
&& printf "configured for %s variant: %s\n" "$ARCH" "$ARCH$SUBARCH"
|
|
|
|
#
|
|
# Some archs (powerpc) have different possible long double formats
|
|
# that the compiler can be configured for. The logic for whether this
|
|
# is supported is in bits/float.h; in general, it is not. We need to
|
|
# check for mismatches here or code in printf, strotd, and scanf will
|
|
# be dangerously incorrect because it depends on (1) the macros being
|
|
# correct, and (2) IEEE semantics.
|
|
#
|
|
printf "checking whether compiler's long double definition matches float.h... "
|
|
echo '#include <float.h>' > "$tmpc"
|
|
echo '#define C(m,s) (m==LDBL_MANT_DIG && s==sizeof(long double))' >> "$tmpc"
|
|
echo 'typedef char ldcheck[(C(53,8)||C(64,12)||C(64,16)||C(113,16))*2-1];' >> "$tmpc"
|
|
if $CC $CFLAGS_C99FSE \
|
|
-I$srcdir/arch/$ARCH -I$srcdir/arch/generic -I$srcdir/include \
|
|
$CPPFLAGS $CFLAGS -c -o /dev/null "$tmpc" >/dev/null 2>&1 ; then
|
|
printf "yes\n"
|
|
else
|
|
printf "no\n"
|
|
fail "$0: error: unsupported long double type"
|
|
fi
|
|
|
|
#
|
|
# Some build systems globally pass in broken CFLAGS like -ffast-math
|
|
# for all packages. On recent GCC we can detect this and error out
|
|
# early rather than producing a seriously-broken math library.
|
|
#
|
|
if trycppif "__FAST_MATH__" \
|
|
"$CFLAGS_C99FSE $CPPFLAGS $CFLAGS" ; then
|
|
fail "$0: error: compiler has broken floating point; check CFLAGS"
|
|
fi
|
|
|
|
printf "creating config.mak... "
|
|
|
|
cmdline=$(quote "$0")
|
|
for i ; do cmdline="$cmdline $(quote "$i")" ; done
|
|
|
|
exec 3>&1 1>config.mak
|
|
|
|
|
|
cat << EOF
|
|
# This version of config.mak was generated by:
|
|
# $cmdline
|
|
# Any changes made here will be lost if configure is re-run
|
|
AR = ${AR:-\$(CROSS_COMPILE)ar}
|
|
RANLIB = ${RANLIB:-\$(CROSS_COMPILE)ranlib}
|
|
ARCH = $ARCH
|
|
SUBARCH = $SUBARCH
|
|
ASMSUBARCH = $ASMSUBARCH
|
|
srcdir = $srcdir
|
|
prefix = $prefix
|
|
exec_prefix = $exec_prefix
|
|
bindir = $bindir
|
|
libdir = $libdir
|
|
includedir = $includedir
|
|
syslibdir = $syslibdir
|
|
CC = $CC
|
|
CFLAGS = $CFLAGS
|
|
CFLAGS_AUTO = $CFLAGS_AUTO
|
|
CFLAGS_C99FSE = $CFLAGS_C99FSE
|
|
CFLAGS_MEMOPS = $CFLAGS_MEMOPS
|
|
CFLAGS_NOSSP = $CFLAGS_NOSSP
|
|
CPPFLAGS = $CPPFLAGS
|
|
LDFLAGS = $LDFLAGS
|
|
LDFLAGS_AUTO = $LDFLAGS_AUTO
|
|
CROSS_COMPILE = $CROSS_COMPILE
|
|
LIBCC = $LIBCC
|
|
OPTIMIZE_GLOBS = $OPTIMIZE_GLOBS
|
|
ALL_TOOLS = $tools
|
|
TOOL_LIBS = $tool_libs
|
|
ADD_CFI = $ADD_CFI
|
|
MALLOC_DIR = $malloc_dir
|
|
EOF
|
|
test "x$static" = xno && echo "STATIC_LIBS ="
|
|
test "x$shared" = xno && echo "SHARED_LIBS ="
|
|
test "x$cc_family" = xgcc && echo 'WRAPCC_GCC = $(CC)'
|
|
test "x$cc_family" = xclang && echo 'WRAPCC_CLANG = $(CC)'
|
|
test "x$pic_default" = xyes && echo 'AOBJS = $(LOBJS)'
|
|
exec 1>&3 3>&-
|
|
|
|
test "$srcdir" = "." || ln -sf $srcdir/Makefile .
|
|
|
|
printf "done\n"
|