http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50963
Bug #: 50963
Summary: TLS incompatible with -mcmodel=large & PIC
Classification: Unclassified
Product: gcc
Version: 4.6.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: drepper....@gmail.com
Due to some build problems with the default models a program was compiled with
-mcmodel=large. But that seems to be incompatible with TLS in PIC. This tiny
code sequence blows up gcc as recently as 4.6.2 (from Fedora rawhide):
__thread int a;
int f(int b)
{
return a;
}
The ICE message when compiled with 'g++ -c -mcmodel=large t.c -fpic' is:
t.c: In function ‘int f(int)’:
t.c:6:1: error: unrecognizable insn:
(call_insn/u 6 5 7 3 (parallel [
(set (reg:DI 0 ax)
(call:DI (mem:QI (symbol_ref:DI ("__tls_get_addr")) [0 S1 A8])
(const_int 0 [0])))
(unspec:DI [
(symbol_ref:DI ("a") [flags 0x10] <var_decl 0x7f55292c31e0
a>)
] UNSPEC_TLS_GD)
]) t.c:5 -1
(expr_list:REG_EH_REGION (const_int -2147483648 [0xffffffff80000000])
(nil))
(nil))
t.c:6:1: internal compiler error: in extract_insn, at recog.c:2109
