[Bug c++/37146] [4.4 Regression] Invalid types with COND_EXPR

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2008-09-10 15:10 -------
I think primarily we want to agree on what is and is not valid lvalue when
bitfields are involved.

int a;
int b;
struct A { int i:8; int j:8; int k:16; int l:32; } c;

void
foo (int x, int y)
{
  (x ? a : b) = y;
  (x ? c.i : c.j) = y;  // error with #c3 patch
  (x ? c.i : a) = y;    // error with #c3 and #c5 patch
  (x ? c.i : c.k) = y;  // error with #c3 and #c5 patch
#if __INT_MAX__ == 2147483647
  (x ? c.l : b) = y;
#endif
}

If all are supposed to be valid, then I fixing this is going to be hard.  We'll
need to create COND_EXPR with mismatching types and then fix it up immediately
once we figure out the COND_EXPR isn't used as lvalue.

The #c3 patch is above, I'll attach another patch as well which allows
bitfields
if they have the same declared type and precision.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37146