PR middle-end/88226 - missing warning on fprintf, fputs, and puts with an unterminated array

gcc/ChangeLog:

	PR middle-end/88226
	* builtins.c (check_nul_terminated_array): New function.
	(fold_builtin_0): Remove declaration.
	(fold_builtin_1): Same.
	(fold_builtin_2): Same.
	(fold_builtin_3): Same.
	(fold_builtin_strpbrk): Add argument.
	(fold_builtin_strspn): Same.
	(fold_builtin_strcspn): Same.
	(expand_builtin_strcat): Call it.  Remove unused argument.
	(expand_builtin_stpncpy): Same.
	(expand_builtin_strncat): Same.
	(expand_builtin_strncpy): Same.  Adjust indentation.
	(expand_builtin_strcmp): Same.
	(expand_builtin_strncmp): Same.
	(expand_builtin_fork_or_exec): Same.
	(expand_builtin): Handle more built-ins.
	(fold_builtin_2): Add argument.
	(fold_builtin_n): Make static.  Add argument.
	(fold_call_expr): Pass new argument to fold_builtin_n and fold_builtin_2.
	(fold_builtin_call_array): Pass new argument to fold_builtin_n.
	(fold_builtin_strpbrk): Add argument.  Call check_nul_terminated_array.
	(fold_call_stmt): Pass new argument to fold_builtin_n.
	* builtins.h: Correct a comment.
	* gimple-fold.c (gimple_fold_builtin_strchr): Call
	check_nul_terminated_array.
	* tree-ssa-strlen.c (handle_builtin_strlen): Call
	check_nul_terminated_array.
	(handle_builtin_strchr): Same.
	(handle_builtin_string_cmp): Same.

gcc/testsuite/ChangeLog:

	PR middle-end/88226
	* gcc.dg/Wstringop-overflow-22.c: New test.
	* gcc.dg/tree-ssa/builtin-fprintf-warn-1.c: Remove xfails.

From-SVN: r278623

1 files changed, 14 insertions, 4 deletions

diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index cfae9db..fadc422 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -1899,6 +1899,11 @@ gimple_fold_builtin_strchr (gimple_stmt_iterator *gsi, bool is_strrchr)
   if (!gimple_call_lhs (stmt))
     return false;
 
+  /* Avoid folding if the first argument is not a nul-terminated array.
+     Defer warning until later.  */
+  if (!check_nul_terminated_array (NULL_TREE, str))
+    return false;
+
   if ((p = c_getstr (str)) && target_char_cst_p (c, &ch))
     {
       const char *p1 = is_strrchr ? strrchr (p, ch) : strchr (p, ch);
@@ -1973,18 +1978,23 @@ static bool
 gimple_fold_builtin_strstr (gimple_stmt_iterator *gsi)
 {
   gimple *stmt = gsi_stmt (*gsi);
+  if (!gimple_call_lhs (stmt))
+    return false;
+
   tree haystack = gimple_call_arg (stmt, 0);
   tree needle = gimple_call_arg (stmt, 1);
-  const char *p, *q;
 
-  if (!gimple_call_lhs (stmt))
+  /* Avoid folding if either argument is not a nul-terminated array.
+     Defer warning until later.  */
+  if (!check_nul_terminated_array (NULL_TREE, haystack)
+      || !check_nul_terminated_array (NULL_TREE, needle))
     return false;
 
-  q = c_getstr (needle);
+  const char *q = c_getstr (needle);
   if (q == NULL)
     return false;
 
-  if ((p = c_getstr (haystack)))
+  if (const char *p = c_getstr (haystack))
     {
       const char *r = strstr (p, q);