diff options
Diffstat (limited to 'gcc/convert.c')
| -rw-r--r-- | gcc/convert.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/gcc/convert.c b/gcc/convert.c index 5680c39df20..03cc098020d 100644 --- a/gcc/convert.c +++ b/gcc/convert.c @@ -608,7 +608,17 @@ convert_to_integer (tree type, tree expr) || ex_form == RSHIFT_EXPR || ex_form == LROTATE_EXPR || ex_form == RROTATE_EXPR)) - || ex_form == LSHIFT_EXPR) + || ex_form == LSHIFT_EXPR + /* If we have !flag_wrapv, and either ARG0 or + ARG1 is of a signed type, we have to do + PLUS_EXPR or MINUS_EXPR in an unsigned + type. Otherwise, we would introduce + signed-overflow undefinedness. */ + || (!flag_wrapv + && (ex_form == PLUS_EXPR + || ex_form == MINUS_EXPR) + && (!TYPE_UNSIGNED (TREE_TYPE (arg0)) + || !TYPE_UNSIGNED (TREE_TYPE (arg1))))) typex = lang_hooks.types.unsigned_type (typex); else typex = lang_hooks.types.signed_type (typex); |