| Message ID | 20150909140254.GF30849@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 09/09/2015 08:02 AM, Marek Polacek wrote: > We were crashing on this testcase in invert_tree_comparison because it > got BIT_AND_EXPR, but this function expects comparison codes only. In > this case pred_equal_p got two predicates: m != 1 and m & 1. By checking > the tcc_comparison first we don't ICE anymore and pred_equal_p correctly > says false for these two predicates. > > In 4.9 we were able to mark 'z' as maybe-uninitialized, but that's likely > out of scope for this patch. > > Bootstrapped/regtested on x86_64-linux, ok for trunk and 5? > > 2015-09-09 Marek Polacek <polacek@redhat.com> > > PR middle-end/67512 > * tree-ssa-uninit.c (pred_equal_p): Only call invert_tree_comparison > for comparisons. > > * gcc.dg/pr67512.c: New test. OK. jeff
diff --git gcc/testsuite/gcc.dg/pr67512.c gcc/testsuite/gcc.dg/pr67512.c index e69de29..628fd71 100644 --- gcc/testsuite/gcc.dg/pr67512.c +++ gcc/testsuite/gcc.dg/pr67512.c @@ -0,0 +1,15 @@ +/* PR middle-end/67512 */ +/* { dg-do compile } */ +/* { dg-options "-O -Wuninitialized" } */ + +extern int fn2 (void); +extern int fn3 (int); +void +fn1 (void) +{ + int z, m; + if (1 & m) /* { dg-warning "is used uninitialized" } */ + z = fn2 (); + z = 1 == m ? z : 2 == m; + fn3 (z); +} diff --git gcc/tree-ssa-uninit.c gcc/tree-ssa-uninit.c index ec6d6f5..fa59642 100644 --- gcc/tree-ssa-uninit.c +++ gcc/tree-ssa-uninit.c @@ -1296,7 +1296,8 @@ pred_equal_p (pred_info x1, pred_info x2) return false; c1 = x1.cond_code; - if (x1.invert != x2.invert) + if (x1.invert != x2.invert + && TREE_CODE_CLASS (x2.cond_code) == tcc_comparison) c2 = invert_tree_comparison (x2.cond_code, false); else c2 = x2.cond_code;