diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/expr.c | 9 |
2 files changed, 14 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 110c0a033e9..73f297442df 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2013-12-10 Eric Botcazou <ebotcazou@adacore.com> + + * expr.c (expand_expr_real_1) <normal_inner_ref>: Always return 0 for + the extraction of a bit-field of null size. + 2013-12-10 Marek Polacek <polacek@redhat.com> PR sanitizer/59437 diff --git a/gcc/expr.c b/gcc/expr.c index f173d032c21..19df9dc0146 100644 --- a/gcc/expr.c +++ b/gcc/expr.c @@ -10157,6 +10157,8 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode, if (target == 0) target = assign_temp (type, 1, 1); + /* ??? Unlike the similar test a few lines below, this one is + very likely obsolete. */ if (bitsize == 0) return target; @@ -10177,6 +10179,13 @@ expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode, return target; } + /* If we have nothing to extract, the result will be 0 for targets + with SHIFT_COUNT_TRUNCATED == 0 and garbage otherwise. Always + return 0 for the sake of consistency, as reading a zero-sized + bitfield is valid in Ada and the value is fully specified. */ + if (bitsize == 0) + return const0_rtx; + op0 = validize_mem (op0); if (MEM_P (op0) && REG_P (XEXP (op0, 0))) |