https://gcc.gnu.org/g:4164c2542952d82e7cdb06d28c8707ac131b5644
commit r14-11468-g4164c2542952d82e7cdb06d28c8707ac131b5644
Author: Jakub Jelinek <ja...@redhat.com>
Date: Wed Mar 12 08:27:17 2025 +0100
builtins: Fix up strspn/strcspn folding [PR119219]
The PR119204 r15-7955 fix caused some regressions.
The problem is that the fold_builtin* APIs document that expr is
either a CALL_EXPR of the call or NULL, so using TREE_TYPE (expr)
can crash e.g. during constexpr evaluation etc.
As can be seen in the surrounding patch, for the neighbouring builtins
(both modf and strpbrk) fold_builtin_2 passes down type, which is the
result type, TREE_TYPE (TREE_TYPE (fndecl)) and those builtins use it
to build the return value, while strspn was always building size_type_node
and strcspn had this change from that to TREE_TYPE (expr).
The patch passes type to these two and uses it there as well.
The patch keeps passing expr because it is used in the
check_nul_terminated_array calls done for both strspn and strcspn,
those calls clearly can deal with NULL expr but prefer if it is non-NULL
for some warning.
2025-03-12 Jakub Jelinek <ja...@redhat.com>
PR middle-end/119204
PR middle-end/119219
* builtins.cc (fold_builtin_2): Pass type as another argument
to fold_builtin_strspn and fold_builtin_strcspn.
(fold_builtin_strspn): Add type argument, use it instead of
size_type_node.
(fold_builtin_strcspn): Add type argument, use it instead of
TREE_TYPE (expr).
(cherry picked from commit da967f0ff324053304b350fdb18384607a346ebd)
Diff:
---
gcc/builtins.cc | 20 +++++++++-----------
1 file changed, 9 insertions(+), 11 deletions(-)
diff --git a/gcc/builtins.cc b/gcc/builtins.cc
index b683c130186e..3e0b590039ff 100644
--- a/gcc/builtins.cc
+++ b/gcc/builtins.cc
@@ -176,8 +176,8 @@ static tree fold_builtin_iseqsig (location_t, tree, tree);
static tree fold_builtin_varargs (location_t, tree, tree*, int);
static tree fold_builtin_strpbrk (location_t, tree, tree, tree, tree);
-static tree fold_builtin_strspn (location_t, tree, tree, tree);
-static tree fold_builtin_strcspn (location_t, tree, tree, tree);
+static tree fold_builtin_strspn (location_t, tree, tree, tree, tree);
+static tree fold_builtin_strcspn (location_t, tree, tree, tree, tree);
static rtx expand_builtin_object_size (tree);
static rtx expand_builtin_memory_chk (tree, rtx, machine_mode,
@@ -10656,10 +10656,10 @@ fold_builtin_2 (location_t loc, tree expr, tree
fndecl, tree arg0, tree arg1)
return fold_builtin_modf (loc, arg0, arg1, type);
case BUILT_IN_STRSPN:
- return fold_builtin_strspn (loc, expr, arg0, arg1);
+ return fold_builtin_strspn (loc, expr, arg0, arg1, type);
case BUILT_IN_STRCSPN:
- return fold_builtin_strcspn (loc, expr, arg0, arg1);
+ return fold_builtin_strcspn (loc, expr, arg0, arg1, type);
case BUILT_IN_STRPBRK:
return fold_builtin_strpbrk (loc, expr, arg0, arg1, type);
@@ -11160,7 +11160,7 @@ fold_builtin_strpbrk (location_t loc, tree, tree s1,
tree s2, tree type)
form of the builtin function call. */
static tree
-fold_builtin_strspn (location_t loc, tree expr, tree s1, tree s2)
+fold_builtin_strspn (location_t loc, tree expr, tree s1, tree s2, tree type)
{
if (!validate_arg (s1, POINTER_TYPE)
|| !validate_arg (s2, POINTER_TYPE))
@@ -11176,8 +11176,7 @@ fold_builtin_strspn (location_t loc, tree expr, tree
s1, tree s2)
if ((p1 && *p1 == '\0') || (p2 && *p2 == '\0'))
/* Evaluate and ignore both arguments in case either one has
side-effects. */
- return omit_two_operands_loc (loc, size_type_node, size_zero_node,
- s1, s2);
+ return omit_two_operands_loc (loc, type, size_zero_node, s1, s2);
return NULL_TREE;
}
@@ -11200,7 +11199,7 @@ fold_builtin_strspn (location_t loc, tree expr, tree
s1, tree s2)
form of the builtin function call. */
static tree
-fold_builtin_strcspn (location_t loc, tree expr, tree s1, tree s2)
+fold_builtin_strcspn (location_t loc, tree expr, tree s1, tree s2, tree type)
{
if (!validate_arg (s1, POINTER_TYPE)
|| !validate_arg (s2, POINTER_TYPE))
@@ -11216,8 +11215,7 @@ fold_builtin_strcspn (location_t loc, tree expr, tree
s1, tree s2)
{
/* Evaluate and ignore argument s2 in case it has
side-effects. */
- return omit_one_operand_loc (loc, TREE_TYPE (expr),
- size_zero_node, s2);
+ return omit_one_operand_loc (loc, type, size_zero_node, s2);
}
/* If the second argument is "", return __builtin_strlen(s1). */
@@ -11231,7 +11229,7 @@ fold_builtin_strcspn (location_t loc, tree expr, tree
s1, tree s2)
if (!fn)
return NULL_TREE;
- return fold_convert_loc (loc, TREE_TYPE (expr),
+ return fold_convert_loc (loc, type,
build_call_expr_loc (loc, fn, 1, s1));
}
return NULL_TREE;
