in theory we could support stack protector in the libc itself, and
users wanting to experiment with such usage could add
-fstack-protector to CFLAGS intentionally. but to avoid breakage in
the default case, override broken distro-patched gcc that forces stack
protector on.
some broken distro-provided toolchains have modified gcc to produce
only "gnu hash" dynamic hash table by default. as this is unsupported
by musl, that results in a non-working libc.so. we detect and switch
this on in configure rather than hard-coding it in the Makefile
because it's not supported by old binutils versions, but that might
not even be relevant since old binutils versions already fail from
-Bsymbolic-functions being missing. at some point I may review whether
this should just go in the Makefile...
this script is not based on autoconf; however it attempts to follow
the same interface contracts for ease of integration with build
systems. it is also not necessary to use musl. manually written
config.mak files are still supported, as is building without any
config.mak at all as long as you are happy with the default options
and you supply at least ARCH on the command line to make.