While testing the proposed patch to eliminate race conditions in indirect value profiling...
http://gcc.gnu.org/ml/gcc-patches/2008-12/msg00892.html I found that the many profile testcases failed due unresolved symbols such as... __emutls_v.__gcov_indirect_call_counters and ___emutls_v.__gcov_indirect_call_callee". A review of the later stage libgcc builds revealed that the -DHAVE_CC_TLS flag was passed without the associated -DUSE_EMUTLS. The current test for setting -DHAVE_CC_TLS is based on the test program... __thread int a; int b; int main() { return a = b; } which while it fails under the Apple system gcc 4.2.1 compiler with the error... thread_test.c:1: error: thread-local storage not supported for this target compiles without error and runs fine under the newly built xgcc compiler (due to the emutls support). The easy fix appears to be... 2010-03-27 Jack Howarth <howa...@bromo.med.uc.edu> * config.host (tmake_file): Add t-emutls for *-*-darwin*. * t-emutls: New file. Index: libgcc/config.host =================================================================== --- libgcc/config.host (revision 157779) +++ libgcc/config.host (working copy) @@ -597,6 +597,12 @@ esac case ${host} in +*-*-darwin*) + tmake_file="${tmake_file} t-emutls" + ;; +esac + +case ${host} in i[34567]86-*-darwin* | x86_64-*-darwin* | \ i[34567]86-*-kfreebsd*-gnu | x86_64-*-kfreebsd*-gnu | \ i[34567]86-*-linux* | x86_64-*-linux* | \ Index: libgcc/config/t-emutls =================================================================== --- libgcc/config/t-emutls (revision 0) +++ libgcc/config/t-emutls (revision 0) @@ -0,0 +1,2 @@ +# Use emulated thread-local storage +INTERNAL_CFLAGS += -DUSE_EMUTLS which bootstraps fine on both x86_64-apple-darwin9 and x86_64-apple-darwin10 with the proposed race condition patch... Index: gcc/tree-profile.c =================================================================== --- gcc/tree-profile.c (revision 157765) +++ gcc/tree-profile.c (working copy) @@ -82,6 +82,7 @@ TREE_PUBLIC (ic_void_ptr_var) = 0; DECL_ARTIFICIAL (ic_void_ptr_var) = 1; DECL_INITIAL (ic_void_ptr_var) = NULL; + DECL_TLS_MODEL (ic_void_ptr_var) = decl_default_tls_model (ic_void_ptr_var); varpool_finalize_decl (ic_void_ptr_var); gcov_type_ptr = build_pointer_type (get_gcov_type ()); @@ -93,6 +94,7 @@ TREE_PUBLIC (ic_gcov_type_ptr_var) = 0; DECL_ARTIFICIAL (ic_gcov_type_ptr_var) = 1; DECL_INITIAL (ic_gcov_type_ptr_var) = NULL; + DECL_TLS_MODEL (ic_gcov_type_ptr_var) = decl_default_tls_model (ic_gcov_type_ptr_var); varpool_finalize_decl (ic_gcov_type_ptr_var); } with no regressions in the testsuite (particularly the profile section). I assume when the race condition fix is committed other targets that use emutls will need to be added to the case statement. -- Summary: libgcc built with -DHAVE_CC_TLS against xgcc when emutls in use Product: gcc Version: 4.5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: howarth at nitro dot med dot uc dot edu GCC build triplet: *-apple-darwin* GCC host triplet: *-apple-darwin* GCC target triplet: *-apple-darwin* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43553
