| Summary: | Missed folding with COMPOUND_EXPR due to C frontend bugs | ||
|---|---|---|---|
| Product: | gcc | Reporter: | Richard Biener <rguenth> |
| Component: | c | Assignee: | Not yet assigned to anyone <unassigned> |
| Status: | NEW --- | ||
| Severity: | normal | Keywords: | diagnostic, missed-optimization |
| Priority: | P3 | ||
| Version: | 13.0 | ||
| Target Milestone: | --- | ||
| Host: | Target: | ||
| Build: | Known to work: | ||
| Known to fail: | Last reconfirmed: | 2022-08-15 00:00:00 | |
Confirmed. |
Doing diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc index 4f4ec81c8d4..698f115507a 100644 --- a/gcc/fold-const.cc +++ b/gcc/fold-const.cc @@ -12595,14 +12595,9 @@ fold_binary_loc (location_t loc, enum tree_code code, tree type, return NULL_TREE; case COMPOUND_EXPR: - /* When pedantic, a compound expression can be neither an lvalue - nor an integer constant expression. */ - if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1)) + if (TREE_SIDE_EFFECTS (arg0)) return NULL_TREE; - /* Don't let (0, 0) be null pointer constant. */ - tem = integer_zerop (arg1) ? build1_loc (loc, NOP_EXPR, type, arg1) - : fold_convert_loc (loc, type, arg1); - return tem; + return op1; case ASSERT_EXPR: /* An ASSERT_EXPR should never be passed to fold_binary. */ results in missed diagnostics: FAIL: gcc.dg/array-5.c bad vla handling (test for bogus messages, line 40) FAIL: gcc.dg/c99-const-expr-12.c (test for excess errors) FAIL: gcc.dg/pr61096-1.c (test for errors, line 29) FAIL: gcc.dg/pr61096-1.c (test for excess errors)