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| author | Richard Guenther <rguenther@suse.de> | 2008-01-16 21:51:57 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2008-01-16 21:51:57 +0000 |
| commit | bdb55eae5e08c10636c8882140b06eeee7921209 (patch) | |
| tree | 31643f94d1c330d6b0c18e681ad5beb86cc4a269 /gcc/fold-const.c | |
| parent | 2e2c7ce23798d0ffd6e1302e1594cf0de8b0bbe7 (diff) | |
| download | gcc-bdb55eae5e08c10636c8882140b06eeee7921209.zip gcc-bdb55eae5e08c10636c8882140b06eeee7921209.tar.gz gcc-bdb55eae5e08c10636c8882140b06eeee7921209.tar.bz2 | |
re PR middle-end/32628 (bogus integer overflow warning)
2008-01-16 Richard Guenther <rguenther@suse.de>
PR middle-end/32628
* fold-const.c (fold_convert_const_int_from_int): Do not
set overflow if that occured only because of a sign extension
change when converting from/to a sizetype with the same
precision and signedness.
* gcc.dg/overflow-warn-7.c: New testcase.
From-SVN: r131579
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 22350b9..ea0b43e 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -2122,8 +2122,22 @@ fold_convert_const_int_from_int (tree type, const_tree arg1) t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1), TREE_INT_CST_HIGH (arg1), /* Don't set the overflow when - converting a pointer */ - !POINTER_TYPE_P (TREE_TYPE (arg1)), + converting from a pointer, */ + !POINTER_TYPE_P (TREE_TYPE (arg1)) + /* or to a sizetype with same signedness + and the precision is unchanged. + ??? sizetype is always sign-extended, + but its signedness depends on the + frontend. Thus we see spurious overflows + here if we do not check this. */ + && !((TYPE_PRECISION (TREE_TYPE (arg1)) + == TYPE_PRECISION (type)) + && (TYPE_UNSIGNED (TREE_TYPE (arg1)) + == TYPE_UNSIGNED (type)) + && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE + && TYPE_IS_SIZETYPE (TREE_TYPE (arg1))) + || (TREE_CODE (type) == INTEGER_TYPE + && TYPE_IS_SIZETYPE (type)))), (TREE_INT_CST_HIGH (arg1) < 0 && (TYPE_UNSIGNED (type) < TYPE_UNSIGNED (TREE_TYPE (arg1)))) |