PR middle-end/93926 - ICE on a built-in redeclaration returning an integer instead of a pointer
gcc/c/ChangeLog:
PR middle-end/93926
* c-decl.c (types_close_enough_to_match): New function.
(match_builtin_function_types):
(diagnose_mismatched_decls): Add missing inform call to a warning.
gcc/testsuite/ChangeLog:
PR middle-end/93926
* gcc.dg/Wbuiltin-declaration-mismatch-13.c: New test.
@@ -1649,6 +1649,18 @@ c_bind (location_t loc, tree decl, bool is_global)
static GTY(()) tree last_structptr_types[6];
+/* Returns true if types T1 and T2 representing return types or types
+ of function arguments are close enough to be considered interchangeable
+ in redeclarations of built-in functions. */
+
+static bool
+types_close_enough_to_match (tree t1, tree t2)
+{
+ return (TYPE_MODE (t1) == TYPE_MODE (t2)
+ && POINTER_TYPE_P (t1) == POINTER_TYPE_P (t2)
+ && FUNCTION_POINTER_TYPE_P (t1) == FUNCTION_POINTER_TYPE_P (t2));
+}
+
/* Subroutine of compare_decls. Allow harmless mismatches in return
and argument types provided that the type modes match. Set *STRICT
and *ARGNO to the expected argument type and number in case of
@@ -1659,16 +1671,19 @@ static tree
match_builtin_function_types (tree newtype, tree oldtype,
tree *strict, unsigned *argno)
{
- /* Accept the return type of the new declaration if same modes. */
- tree oldrettype = TREE_TYPE (oldtype);
- tree newrettype = TREE_TYPE (newtype);
-
*argno = 0;
*strict = NULL_TREE;
- if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
+ /* Accept the return type of the new declaration if it has the same
+ mode and if they're both pointers or if neither is. */
+ tree oldrettype = TREE_TYPE (oldtype);
+ tree newrettype = TREE_TYPE (newtype);
+
+ if (!types_close_enough_to_match (oldrettype, newrettype))
return NULL_TREE;
+ /* Check that the return types are compatible but don't fail if they
+ are not (e.g., int vs long in ILP32) and just let the caller know. */
if (!comptypes (TYPE_MAIN_VARIANT (oldrettype),
TYPE_MAIN_VARIANT (newrettype)))
*strict = oldrettype;
@@ -1692,15 +1707,7 @@ match_builtin_function_types (tree newtype, tree oldtype,
tree oldtype = TYPE_MAIN_VARIANT (TREE_VALUE (oldargs));
tree newtype = TYPE_MAIN_VARIANT (TREE_VALUE (newargs));
- /* Fail for types with incompatible modes/sizes. */
- if (TYPE_MODE (TREE_VALUE (oldargs))
- != TYPE_MODE (TREE_VALUE (newargs)))
- return NULL_TREE;
-
- /* Fail for function and object pointer mismatches. */
- if ((FUNCTION_POINTER_TYPE_P (oldtype)
- != FUNCTION_POINTER_TYPE_P (newtype))
- || POINTER_TYPE_P (oldtype) != POINTER_TYPE_P (newtype))
+ if (!types_close_enough_to_match (oldtype, newtype))
return NULL_TREE;
unsigned j = (sizeof (builtin_structptr_types)
@@ -1957,11 +1964,10 @@ diagnose_mismatched_decls (tree newdecl, tree olddecl,
&& !C_DECL_DECLARED_BUILTIN (olddecl))
{
/* Accept "harmless" mismatches in function types such
- as missing qualifiers or pointer vs same size integer
- mismatches. This is for the ffs and fprintf builtins.
- However, with -Wextra in effect, diagnose return and
- argument types that are incompatible according to
- language rules. */
+ as missing qualifiers or int vs long when they're the same
+ size. However, with -Wextra in effect, diagnose return and
+ argument types that are incompatible according to language
+ rules. */
tree mismatch_expect;
unsigned mismatch_argno;
@@ -1999,16 +2005,25 @@ diagnose_mismatched_decls (tree newdecl, tree olddecl,
/* If types match only loosely, print a warning but accept
the redeclaration. */
location_t newloc = DECL_SOURCE_LOCATION (newdecl);
+ bool warned = false;
if (mismatch_argno)
- warning_at (newloc, OPT_Wbuiltin_declaration_mismatch,
- "mismatch in argument %u type of built-in "
- "function %qD; expected %qT",
- mismatch_argno, newdecl, mismatch_expect);
+ warned = warning_at (newloc, OPT_Wbuiltin_declaration_mismatch,
+ "mismatch in argument %u type of built-in "
+ "function %qD; expected %qT",
+ mismatch_argno, newdecl, mismatch_expect);
else
- warning_at (newloc, OPT_Wbuiltin_declaration_mismatch,
- "mismatch in return type of built-in "
- "function %qD; expected %qT",
- newdecl, mismatch_expect);
+ warned = warning_at (newloc, OPT_Wbuiltin_declaration_mismatch,
+ "mismatch in return type of built-in "
+ "function %qD; expected %qT",
+ newdecl, mismatch_expect);
+ const char *header = header_for_builtin_fn (olddecl);
+ if (warned && header)
+ {
+ rich_location richloc (line_table, newloc);
+ maybe_add_include_fixit (&richloc, header, true);
+ inform (&richloc,
+ "%qD is declared in header %qs", olddecl, header);
+ }
}
}
else if (TREE_CODE (olddecl) == FUNCTION_DECL
new file mode 100644
@@ -0,0 +1,78 @@
+/* PR middle-end/93926 - ICE on a built-in redeclaration returning an integer
+ instead of a pointer
+ { dg-do compile }
+ { dg-options "-Wall" } */
+
+typedef __SIZE_TYPE__ size_t;
+
+void* ret_calloc (size_t n1, size_t n2)
+{
+ extern size_t calloc (size_t, size_t); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return (void *) calloc (n1, n2);
+}
+
+void* ret_malloc (size_t n)
+{
+ extern size_t malloc (size_t); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return (void *) malloc (n);
+}
+
+void* ret_realloc (void *p, size_t n)
+{
+ extern size_t realloc (void *p, size_t); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return (void *) realloc (p, n);
+}
+
+void* ret_strdup (const char *s)
+{
+ extern size_t strdup (const char*); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return (void *) strdup (s);
+}
+
+void* ret_strndup (const char *s, size_t n)
+{
+ extern size_t
+ strndup (const char*, size_t); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return (void *) strndup (s, n);
+}
+
+// For good measure also exerise strcmp return type (not part of the bug).
+
+char* ret_strcmp (const char *s, const char *t)
+{
+ extern char*
+ strcmp (const char*, const char*); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return strcmp (s, t);
+}
+
+// Exercise warnings for pointer/integer mismatches in argument types
+// (also not part of the bug).
+
+char* ret_strcat (size_t s, const char *t)
+{
+ extern char*
+ strcat (size_t, const char*); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return strcat (s, t);
+}
+
+char* ret_strcpy (char *s, size_t t)
+{
+ extern char* strcpy (char*, size_t); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return strcpy (s, t);
+}
+
+char* ret_strncpy (char *s, const char *t, size_t n)
+{
+ extern char*
+ strncpy (char*, size_t, const char*); // { dg-warning "\\\[-Wbuiltin-declaration-mismatch" }
+
+ return strncpy (s, n, t);
+}