Description of problem:
This little piece of code ICEs gcc when compiled for x86:

long long a;
void f(long long b) {
  __sync_bool_compare_and_swap (&a, 1, b);
}

It is necessary to add -march=i686 to the command line to enable using cmpxchg8b.


Version-Release number of selected component (if applicable):
4.1.1-30
4.1.1-45

How reproducible:
always when compiling on x86-64 with -m32
haven't tried native x86

Steps to Reproduce:
1.gcc -S -m32 ice.c -march=i686
2.
3.
  
Actual results:
u.c: In function ‘f’:
u.c:3: internal compiler error: Segmentation fault


Expected results:
Code using cmpxchg8b

Additional info: