diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 32de681..1a1a80f 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -2327,7 +2327,24 @@ fold_convert_const_real_from_real (tree type, const_tree arg1) real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1)); t = build_real (type, value); - TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1); + /* If converting an infinity or NAN to a representation that doesn't + have one, set the overflow bit so that we can produce some kind of + error message at the appropriate point if necessary. It's not the + most user-friendly message, but it's better than nothing. */ + if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1)) + && !MODE_HAS_INFINITIES (TYPE_MODE (type))) + TREE_OVERFLOW (t) = 1; + else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1)) + && !MODE_HAS_NANS (TYPE_MODE (type))) + TREE_OVERFLOW (t) = 1; + /* Regular overflow, conversion produced an infinity in a mode that + can't represent them. */ + else if (!MODE_HAS_INFINITIES (TYPE_MODE (type)) + && REAL_VALUE_ISINF (value) + && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1))) + TREE_OVERFLOW (t) = 1; + else + TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1); return t; } |