This doesn't seem to affect me using GCC 6.1 and gold <div class="gmail_quote"><div dir="ltr">On Thu, 2 Jun 2016, 6:42 p.m. Jan Ziak (⚛), <<a href="mailto:0xe2.0x9a.0x9b@gmail.com">0xe2.0x9a.0x9b@gmail.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">LTO compilation can sometimes fail with GCC 4.9 and GCC 5.3 because src/mapi uses unusual mixing of C code and assembly code. The issue may be present in case of GCC 6.1 as well. This is a Mesa bug rather than a compiler bug (although in an ideal world the compilation with -flto should fail if and only if normal compilation fails). The error message: entry_x86-64_tls.h:61: undefined reference to `x86_64_entry_start' Without the patch: - using "-flto -O2 -DDEBUG" fails with GCC 4.9 and 5.3 - using "-flto -O3 -DDEBUG" succeeds with GCC 4.9 and 5.3 - using "-flto -O2 -DNDEBUG" succeeds with GCC 4.9 and 5.3 The patch assumes that the assembler understands ".hidden" directive. Signed-off-by: Jan Ziak (⚛) <<a href="mailto:0xe2.0x9a.0x9b@gmail.com" target="_blank">0xe2.0x9a.0x9b@gmail.com</a>> --- src/mapi/entry_x86-64_tls.h | 5 +++-- src/mapi/entry_x86_tls.h | 12 +++++++++--- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/src/mapi/entry_x86-64_tls.h b/src/mapi/entry_x86-64_tls.h index 38faccc..acabecc 100644 --- a/src/mapi/entry_x86-64_tls.h +++ b/src/mapi/entry_x86-64_tls.h @@ -28,6 +28,8 @@ __asm__(".text\n" ".balign 32\n" + ".globl x86_64_entry_start\n" + ".hidden x86_64_entry_start\n" "x86_64_entry_start:"); #define STUB_ASM_ENTRY(func) \ @@ -54,8 +56,7 @@ entry_patch_public(void) { } -static char -x86_64_entry_start[]; +extern char x86_64_entry_start[]; mapi_func entry_get_public(int slot) diff --git a/src/mapi/entry_x86_tls.h b/src/mapi/entry_x86_tls.h index 46d2ece..6078b9a 100644 --- a/src/mapi/entry_x86_tls.h +++ b/src/mapi/entry_x86_tls.h @@ -29,7 +29,9 @@ __asm__(".text"); -__asm__("x86_current_tls:\n\t" +__asm__( ".globl x86_current_tls\n" + ".hidden x86_current_tls\n" + "x86_current_tls:\n\t" "call 1f\n" "1:\n\t" "popl %eax\n\t" @@ -42,6 +44,8 @@ __asm__(".section wtext, \"awx\", @progbits"); #endif /* GLX_X86_READONLY_TEXT */ __asm__(".balign 16\n" + ".globl x86_entry_start\n" + ".hidden x86_entry_start\n" "x86_entry_start:"); #define STUB_ASM_ENTRY(func) \ @@ -60,6 +64,8 @@ __asm__(".balign 16\n" #ifndef GLX_X86_READONLY_TEXT __asm__(".balign 16\n" + ".globl x86_entry_end\n" + ".hidden x86_entry_end\n" "x86_entry_end:"); __asm__(".text"); #endif /* GLX_X86_READONLY_TEXT */ @@ -71,8 +77,8 @@ __asm__(".text"); extern unsigned long x86_current_tls(); -static char x86_entry_start[]; -static char x86_entry_end[]; +extern char x86_entry_start[]; +extern char x86_entry_end[]; void entry_patch_public(void) -- 2.8.3 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org" target="_blank">mesa-dev@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div>