mirror of git://git.musl-libc.org/musl
610c5a8524
In TLS variant I the TLS is above TP (or above a fixed offset from TP) but on some targets there is a reserved gap above TP before TLS starts. This matters for the local-exec tls access model when the offsets of TLS variables from the TP are hard coded by the linker into the executable, so the libc must compute these offsets the same way as the linker. The tls offset of the main module has to be alignup(GAP_ABOVE_TP, main_tls_align). If there is no TLS in the main module then the gap can be ignored since musl does not use it and the tls access models of shared libraries are not affected. The previous setup only worked if (tls_align & -GAP_ABOVE_TP) == 0 (i.e. TLS did not require large alignment) because the gap was treated as a fixed offset from TP. Now the TP points at the end of the pthread struct (which is aligned) and there is a gap above it (which may also need alignment). The fix required changing TP_ADJ and __pthread_self on affected targets (aarch64, arm and sh) and in the tlsdesc asm the offset to access the dtv changed too. |
||
---|---|---|
arch | ||
crt | ||
dist | ||
include | ||
ldso | ||
src | ||
tools | ||
.gitignore | ||
COPYRIGHT | ||
INSTALL | ||
Makefile | ||
README | ||
VERSION | ||
WHATSNEW | ||
configure | ||
dynamic.list |
README
musl libc musl, pronounced like the word "mussel", is an MIT-licensed implementation of the standard C library targetting the Linux syscall API, suitable for use in a wide range of deployment environments. musl offers efficient static and dynamic linking support, lightweight code and low runtime overhead, strong fail-safe guarantees under correct usage, and correctness in the sense of standards conformance and safety. musl is built on the principle that these goals are best achieved through simple code that is easy to understand and maintain. The 1.1 release series for musl features coverage for all interfaces defined in ISO C99 and POSIX 2008 base, along with a number of non-standardized interfaces for compatibility with Linux, BSD, and glibc functionality. For basic installation instructions, see the included INSTALL file. Information on full musl-targeted compiler toolchains, system bootstrapping, and Linux distributions built on musl can be found on the project website: http://www.musl-libc.org/