* H.J. Lu <hjl.to...@gmail.com> [2015-05-09 10:41:41 -0700]: > On Sat, May 9, 2015 at 7:31 AM, Szabolcs Nagy <n...@port70.net> wrote: > > > > The symbol versioning hack for __cpu_model and __cpu_indicator_init > > makes them invisible to the musl dynamic linker so their relocation > > fails with 'symbol not found' error. > > (affects anything linked with -lgcc_s) > > There are > > 4: 0000000000002b70 806 FUNC GLOBAL DEFAULT 12 > __cpu_indicator_init@GCC_4.8.0 > 38: 00000000002153d0 16 OBJECT GLOBAL DEFAULT 25 > __cpu_model@GCC_4.8.0 > > and > > 000000000215000 0000000400000001 R_X86_64_64 > 0000000000002b70 __cpu_indicator_init@GCC_4.8.0 + 0 > 0000000000215220 0000002600000006 R_X86_64_GLOB_DAT > 00000000002153d0 __cpu_model@GCC_4.8.0 + 0 > > in libgcc_s.so.1. Musl ld.so must be fixed to handle it. >
(sorry, i missed the other discussion about the same issue) i still think a solution that avoids depending on symbol versioning in the dynamic linker would be preferable. (versioning is a sun/gnu elf extension as far as i understand, eg. not supported by posix dlsym). i think it might be enough to add __cpu_indicator_init_local as an alias to __cpu_indicator_init in libgcc.a and then use the *_local symbol from the ifunc resolver, that way no new dependency is added to libgcc_s.so handling. (adding versioning support to musl is problematic with the current code, a simpler workaround for musl is to provide its own weak definition of __cpu_indicator_init, but that's ugly.)
