From 9b6c937b0041de8b65a6f11db9c5a05efd3fd7c6 Mon Sep 17 00:00:00 2001 From: Stan Shebs Date: Tue, 25 Sep 2018 07:20:18 -0700 Subject: Add workaround for segfaults in __longjmp when compiled with ppc clang --- elf/dl-error-skeleton.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'elf') diff --git a/elf/dl-error-skeleton.c b/elf/dl-error-skeleton.c index d5f418a..01870c5 100644 --- a/elf/dl-error-skeleton.c +++ b/elf/dl-error-skeleton.c @@ -85,6 +85,21 @@ fatal_error (int errcode, const char *objname, const char *occasion, : "")); } +/* Due to a complicated set of interactions with different symbol + versions, presumably including a VMX-specific __vmx__longjmp, PPC + clang ends calling __longjump with ld.so through the global entry + point (+0x0) instead of via the local entry point (+0x8) which + results in ld.so exceptions crashing because the TOC is not set up. + The hack here simply calls the function through a pointer, which + guarantees that the global entry point has the TOC set up. (This + may or may not be a clang bug, the symbol aliasing is tricky and + literally affects only __longjmp out of all the symbols in + libc.) */ +#if defined __clang__ && defined __powerpc64__ +volatile void (*longjmpptr) (struct __jmp_buf_tag __env[1], int __val) +__attribute__ ((__nothrow__)) __attribute__ ((__noreturn__)) = __longjmp; +#endif + void _dl_signal_exception (int errcode, struct dl_exception *exception, const char *occasion) @@ -96,7 +111,11 @@ _dl_signal_exception (int errcode, struct dl_exception *exception, *lcatch->errcode = errcode; /* We do not restore the signal mask because none was saved. */ +#if defined __clang__ && defined __powerpc64__ + (*longjmpptr) (lcatch->env[0].__jmpbuf, 1); +#else __longjmp (lcatch->env[0].__jmpbuf, 1); +#endif } else fatal_error (errcode, exception->objname, occasion, exception->errstring); @@ -118,7 +137,11 @@ _dl_signal_error (int errcode, const char *objname, const char *occation, *lcatch->errcode = errcode; /* We do not restore the signal mask because none was saved. */ +#if defined __clang__ && defined __powerpc64__ + (*longjmpptr) (lcatch->env[0].__jmpbuf, 1); +#else __longjmp (lcatch->env[0].__jmpbuf, 1); +#endif } else fatal_error (errcode, objname, occation, errstring); -- cgit v1.1