PATCH: Fix implementation of __aeabi_vec*

Mark Mitchell mark@codesourcery.com
Fri Jun 27 23:15:00 GMT 2008


The ARM ABI C++ vector helper functions are required to accept NULL
pointers as inputs -- but the implementation in libsupc++ did not do
that.  We don't use these functions from code generated by G++, but
other compilers do call them.  This simple patch fixes the problem.

Committed to mainline.

As an FYI, I'm also working on a patch to use the generic helper
functions (though not the special ARM versions) when optimizing for
size.

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713

2008-06-27  Mark Mitchell  <mark@codesourcery.com>

	* libsupc++/vec.cc (__aeabi_vec_dtor_cookie): Handle NULL array
	address.
	(__aeabi_vec_delete): Likewise.
	(__aeabi_vec_delete3): Likewise.
	(__aeabi_vec_delete3_nodtor): Likewise.

2008-06-27  Mark Mitchell  <mark@codesourcery.com>

	* g++.dg/abi/arm_cxa_vec2.C: New test.

Index: libstdc++-v3/libsupc++/vec.cc
===================================================================
--- libstdc++-v3/libsupc++/vec.cc	(revision 137206)
+++ libstdc++-v3/libsupc++/vec.cc	(working copy)
@@ -461,6 +461,9 @@ namespace __aeabiv1
   __aeabi_vec_dtor_cookie (void *array_address, 
 			   abi::__cxa_cdtor_type destructor)
   {
+    if (!array_address)
+      return NULL;
+
     abi::__cxa_vec_dtor (array_address, 
 			 reinterpret_cast<std::size_t *>(array_address)[-1],
 			 reinterpret_cast<std::size_t *>(array_address)[-2],
@@ -473,6 +476,9 @@ namespace __aeabiv1
   __aeabi_vec_delete (void *array_address, 
 		      abi::__cxa_cdtor_type destructor)
   {
+    if (!array_address)
+      return;
+
     abi::__cxa_vec_delete (array_address,
 			   reinterpret_cast<std::size_t *>(array_address)[-2],
 			   2 * sizeof (std::size_t),
@@ -484,6 +490,9 @@ namespace __aeabiv1
 		       abi::__cxa_cdtor_type destructor,
 		       void (*dealloc) (void *, std::size_t))
   {
+    if (!array_address)
+      return;
+
     abi::__cxa_vec_delete3 (array_address,
 			    reinterpret_cast<std::size_t *>(array_address)[-2],
 			    2 * sizeof (std::size_t),
@@ -494,6 +503,9 @@ namespace __aeabiv1
   __aeabi_vec_delete3_nodtor (void *array_address,
 			      void (*dealloc) (void *, std::size_t))
   {
+    if (!array_address)
+      return;
+
     abi::__cxa_vec_delete3 (array_address,
 			    reinterpret_cast<std::size_t *>(array_address)[-2],
 			    2 * sizeof (std::size_t),
Index: gcc/testsuite/g++.dg/abi/arm_cxa_vec2.C
===================================================================
--- gcc/testsuite/g++.dg/abi/arm_cxa_vec2.C	(revision 0)
+++ gcc/testsuite/g++.dg/abi/arm_cxa_vec2.C	(revision 0)
@@ -0,0 +1,41 @@
+// Check that ARM vector delete functions accept NULL pointers as
+// inputs.
+// { dg-do run { target arm*-*-* } }
+
+#ifdef __ARM_EABI__
+#include <cxxabi.h>
+
+typedef void *(dtor_type)(void *);
+
+extern "C" {
+  void abort();
+  void *__aeabi_vec_dtor_cookie(void *, dtor_type);
+  void __aeabi_vec_delete(void *, dtor_type);
+  void __aeabi_vec_delete3(void *, 
+			   dtor_type, 
+			   void (*)(void *, __SIZE_TYPE__));
+  void __aeabi_vec_delete3_nodtor(void *, 
+				  void (*)(void *, __SIZE_TYPE__));
+}
+
+// These functions should never be called.
+void* dtor(void *)
+{
+  abort ();
+}
+
+void dealloc(void *, size_t) {
+  abort ();
+}
+
+int main () {
+  if (__aeabi_vec_dtor_cookie (NULL, &dtor) != NULL)
+    return 1;
+  // These do not return values, but should not crash.
+  __aeabi_vec_delete (NULL, &dtor);
+  __aeabi_vec_delete3 (NULL, &dtor, &dealloc);
+  __aeabi_vec_delete3_nodtor (NULL, &dealloc);
+}
+#else
+int main () {}
+#endif



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