PR middle-end/89957 - ICE calling strnlen with an int128_t bound in a known range
PR middle-end/89911 - [9 Regression] ICE in get_attr_nonstring_decl
gcc/ChangeLog:
PR middle-end/89957
PR middle-end/89911
* builtins.c (expand_builtin_strnlen): Make sure wi::ltu_p operands
have the same precision since the function crashes otherwise.
* calls.c (maybe_warn_nonstring_arg): Avoid assuming strnlen() call
has non-zero arguments.
gcc/testsuite/ChangeLog:
PR middle-end/89957
PR middle-end/89911
* gcc.dg/Wstringop-overflow-13.c: New test.
===================================================================
@@ -3151,7 +3151,7 @@ expand_builtin_strnlen (tree exp, rtx target, mach
return NULL_RTX;
if (!TREE_NO_WARNING (exp)
- && wi::ltu_p (wi::to_wide (maxobjsize), min)
+ && wi::ltu_p (wi::to_wide (maxobjsize, min.get_precision ()), min)
&& warning_at (loc, OPT_Wstringop_overflow_,
"%K%qD specified bound [%wu, %wu] "
"exceeds maximum object size %E",
===================================================================
@@ -1555,7 +1555,10 @@ maybe_warn_nonstring_arg (tree fndecl, tree exp)
if (TREE_NO_WARNING (exp) || !warn_stringop_overflow)
return;
+ /* Avoid clearly invalid calls (more checking done below). */
unsigned nargs = call_expr_nargs (exp);
+ if (!nargs)
+ return;
/* The bound argument to a bounded string function like strncpy. */
tree bound = NULL_TREE;
===================================================================
@@ -0,0 +1,40 @@
+/* PR middle-end/89957 - ICE calling strnlen with an int128_t bound
+ in a known range
+ PR middle-end/89911 - ICE on a call with no arguments to strnlen
+ declared with no prototype
+ { dg-do compile }
+ { dg-options "-O2 -Wall" } */
+
+typedef __SIZE_TYPE__ size_t;
+
+extern size_t strnlen ();
+
+size_t f0 (void)
+{
+ return strnlen (); /* { dg-warning "too few arguments to built-in function 'strnlen'" } */
+}
+
+size_t f1 (const char *s)
+{
+ return strnlen (s); /* { dg-warning "too few arguments to built-in function 'strnlen'" } */
+}
+
+size_t f2 (const char *s)
+{
+ return strnlen (s, s); /* { dg-warning "\\\[-Wint-conversion]" } */
+}
+
+#if __SIZEOF_INT128__ == 16
+
+size_t fi128 (const char *s, __int128_t n)
+{
+ if (n < 0)
+ n = 0;
+
+ /* PR middle-end/89957 */
+ return strnlen (s, n); /* { dg-warning "\\\[-Wbuiltin-declaration-mismatch]" "int128" { target int128 } } */
+}
+
+#endif
+
+/* { dg-prune-output "\\\[-Wint-conversion]" } */
Attached is yet another patch to avoid ICE due to middle-end assumptions about the sanity of calls to built-ins, this time for strnlen. It fixes two unsafe assumptions: 1) The -Wstringop-overflow checker for unterminated constant char arrays assumes that strnlen is called with exactly two arguments. When the function is declared without a prototype and called with no arguments the code aborts. This is PR 89911 (P1). 2) The wide_int min/max values of get_range_info() called on the strnlen bound have the same precision as PTRDIFF_MAX. That's not so when strnlen is declared without a prototype and called with an int128_t argument in some range. Rather than handling this case, wi::ltu_p() helpfully aborts instead. This is PR 89957 that I exposed while testing the fix above. The trivial patch avoids both of these assumptions. It's been tested on x86_64-linux. Similar to the patch for PR 89934, I will commit it later this week unless there are objections. Martin Patch for PR 89934 for reference: https://gcc.gnu.org/ml/gcc-patches/2019-04/msg00149.html