On Tue, Aug 18, 2015 at 10:47:44AM +0200, Richard Biener wrote:
> On Mon, Aug 17, 2015 at 8:01 PM, Marek Polacek <pola...@redhat.com> wrote:
> > Here we were crashing on an invalid call to posix_memalign. The code in
> > lower_builtin_posix_memalign assumed that the call had valid arguments.
> > The reason the C FE doesn't reject this code is, in short, that
> > int <T> () is compatible with int <T> (void **, size_t, size_t) and we
> > use the former -- so convert_arguments doesn't complain.
> >
> > So I think let's validate the arguments in lower_stmt. I decided to
> > give an error if we see an invalid usage of posix_memalign, since
> > other code (e.g. alias machinery) assumes correct arguments as well.
> >
> > Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> I don't think you can give errors here. Note that the "appropriate"
> way to do the check is to simply use
Yeah, because the weirdo call is only undefined if it's reached at runtime,
right.
> if (gimple_builtin_call_types_compatible_p (stmt, decl))
Nice, dunno how could I not find that.
> not lowering in case it's not compatible is ok.
In that case I also need to check a place in tree-ssa-alias.c.
Bootstrapped/regtested on x86_64-linux, ok for trunk and 5?
2015-08-18 Marek Polacek <pola...@redhat.com>
PR middle-end/67222
* gimple-low.c (lower_stmt): Check the posix_memalign call.
* tree-ssa-alias.c (call_may_clobber_ref_p_1): Likewise.
* gcc.dg/torture/pr67222.c: New test.
diff --git gcc/gimple-low.c gcc/gimple-low.c
index d4697e2..4eae3a0 100644
--- gcc/gimple-low.c
+++ gcc/gimple-low.c
@@ -346,7 +346,8 @@ lower_stmt (gimple_stmt_iterator *gsi, struct lower_data
*data)
return;
}
else if (DECL_FUNCTION_CODE (decl) == BUILT_IN_POSIX_MEMALIGN
- && flag_tree_bit_ccp)
+ && flag_tree_bit_ccp
+ && gimple_builtin_call_types_compatible_p (stmt, decl))
{
lower_builtin_posix_memalign (gsi);
return;
diff --git gcc/testsuite/gcc.dg/torture/pr67222.c
gcc/testsuite/gcc.dg/torture/pr67222.c
index e69de29..739f869 100644
--- gcc/testsuite/gcc.dg/torture/pr67222.c
+++ gcc/testsuite/gcc.dg/torture/pr67222.c
@@ -0,0 +1,19 @@
+/* PR middle-end/67222 */
+/* { dg-do compile } */
+
+void
+foo (void **p)
+{
+ posix_memalign (); /* { dg-warning "implicit declaration" } */
+ posix_memalign (p);
+ posix_memalign (0);
+ posix_memalign (p, 1);
+ posix_memalign (p, "foo");
+ posix_memalign ("gnu", "gcc");
+ posix_memalign (1, p);
+ posix_memalign (1, 2);
+ posix_memalign (1, 2, 3);
+ posix_memalign (p, p, p);
+ posix_memalign (p, "qui", 3);
+ posix_memalign (p, 1, 2);
+}
diff --git gcc/tree-ssa-alias.c gcc/tree-ssa-alias.c
index e103220..e96a00c 100644
--- gcc/tree-ssa-alias.c
+++ gcc/tree-ssa-alias.c
@@ -2039,6 +2039,10 @@ call_may_clobber_ref_p_1 (gcall *call, ao_ref *ref)
by its first argument. */
case BUILT_IN_POSIX_MEMALIGN:
{
+ /* For weirdo calls we cannot say much so stay conservative. */
+ tree decl = gimple_call_fndecl (call);
+ if (!gimple_builtin_call_types_compatible_p (call, decl))
+ return true;
tree ptrptr = gimple_call_arg (call, 0);
ao_ref dref;
ao_ref_init_from_ptr_and_size (&dref, ptrptr,
Marek
