[Bug middle-end/127326] New: [x86_32] error: inconsistent operand constraints in an 'asm'

[ubizjak at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127326

            Bug ID: 127326
           Summary: [x86_32] error: inconsistent operand constraints in an
                    'asm'
           Product: gcc
           Version: 16.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ubizjak at gmail dot com
  Target Milestone: ---

The following testcase:

--cut here--
_Decimal128 test (void)
{
  union { _Decimal128 d; unsigned long long u[2]; } u;
  u.d = 1.0DL;
  __asm ("" : "+g" (u.d));
  return u.d;
}
--cut here--

fails to compile with on i686 with -O2:

$ gcc -O2 -m32 inout.c 
inout.c: In function ‘test’:
inout.c:5:3: error: inconsistent operand constraints in an ‘asm’
    5 |   __asm ("" : "+g" (u.d));
      |   ^~~~~

The testcase compiles OK for x86_64.