http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57434
Bug ID: 57434
Summary: [4.7 regression] -fprofile-arcs introduces unused TLS
variables
Product: gcc
Version: 4.7.4
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: ro at gcc dot gnu.org
CC: richard.guenther at gmail dot com
Host: *-*-solaris2.[89]
Target: *-*-solaris2.[89]
Build: *-*-solaris2.[89]
I only now noticed that several -fprofile-arcs testcases started to FAIL on
Solaris 8 and 9 with TLS support, e.g.
FAIL: gcc.misc-tests/gcov-1.c execution test
FAIL: gcc.misc-tests/gcov-1.c gcov failed: gcov-1.c.gov does not exist
The testcase tails to execute with
% gcc/xgcc -Bgcc/
/vol/gcc/src/hg/gcc-4.7-branch/solaris/gcc/testsuite/gcc.misc-tests/gcov-1.c
-fprofile-arcs -ftest-coverage -lm -o ./gcov-1.exe
% ./gcov-1.exe
ld.so.1: gcov-1.exe: fatal: gcov-1.exe: object requires TLS, but TLS failed to
initialize
Killed
A reghunt discovered that this is a regression introduced by this patch:
2012-09-11 Richard Guenther <rguent...@suse.de>
PR debug/54534
* cgraph.h (varpool_can_remove_if_no_refs): Restore dependence
on flag_toplevel_reorder.
With it, gcov-1.s gains two unused definitions of TLS variables:
ro@luole 185 > diff -u 88*/*.s
--- 880/gcov-1.s 2013-05-27 16:07:38.106783000 +0200
+++ 881/gcov-1.s 2013-05-27 16:07:32.227394000 +0200
@@ -70,10 +70,23 @@
.cfi_endproc
.LFE1:
.size main, .-main
+ .section .tbss,"awT",@nobits
+ .align 4
+ .type __gcov_indirect_call_callee, @object
+ .size __gcov_indirect_call_callee, 4
+__gcov_indirect_call_callee:
+ .zero 4
+ .align 4
+ .type __gcov_indirect_call_counters, @object
+ .size __gcov_indirect_call_counters, 4
+__gcov_indirect_call_counters:
+ .zero 4
.local __gcov0.main
+ .bss
.comm __gcov0.main,24,8
.comm __gcov0.noop,8,8
+ .text
.type _GLOBAL__sub_I_65535_0_noop, @function
_GLOBAL__sub_I_65535_0_noop:
.LFB2:
As a bad Solaris-specific hack, one could handle -fprofile-arcs like
-fprofile-generate in config/sol2.h LIB_SPEC and LINK_SPEC, but it would be
better to fix the underlying problem.
Rainer
.local __gcov0.noop
