ubsan: Avoid -Wpadded warnings [PR94641]

-Wpadded warnings aren't really useful for the artificial types that GCC
lays out for ubsan.

2020-04-21  Jakub Jelinek  <jakub@redhat.com>

	PR c/94641
	* stor-layout.c (place_field, finalize_record_size): Don't emit
	-Wpadded warning on TYPE_ARTIFICIAL rli->t.
	* ubsan.c (ubsan_get_type_descriptor_type,
	ubsan_get_source_location_type, ubsan_create_data): Set
	TYPE_ARTIFICIAL.
	* asan.c (asan_global_struct): Likewise.

	* c-c++-common/ubsan/pr94641.c: New test.

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index dc831f6..90c13ae 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2020-04-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c/94641
+       * stor-layout.c (place_field, finalize_record_size): Don't emit
+       -Wpadded warning on TYPE_ARTIFICIAL rli->t.
+       * ubsan.c (ubsan_get_type_descriptor_type,
+       ubsan_get_source_location_type, ubsan_create_data): Set
+       TYPE_ARTIFICIAL.
+       * asan.c (asan_global_struct): Likewise.
+
 2020-04-21  Duan bo  <duanbo3@huawei.com>
 
        PR target/94577

diff --git a/gcc/asan.c b/gcc/asan.c
index cc8f912..ae14f7e 100644 (file)
--- a/gcc/asan.c
+++ b/gcc/asan.c
@@ -2661,6 +2661,7 @@ asan_global_struct (void)
   TYPE_FIELDS (ret) = fields[0];
   TYPE_NAME (ret) = type_decl;
   TYPE_STUB_DECL (ret) = type_decl;
+  TYPE_ARTIFICIAL (ret) = 1;
   layout_type (ret);
   return ret;
 }

diff --git a/gcc/stor-layout.c b/gcc/stor-layout.c
index 8c9e034..bde6fa2 100644 (file)
--- a/gcc/stor-layout.c
+++ b/gcc/stor-layout.c
@@ -1341,7 +1341,8 @@ place_field (record_layout_info rli, tree field)
         Bump the cumulative size to multiple of field alignment.  */
 
       if (!targetm.ms_bitfield_layout_p (rli->t)
-          && DECL_SOURCE_LOCATION (field) != BUILTINS_LOCATION)
+         && DECL_SOURCE_LOCATION (field) != BUILTINS_LOCATION
+         && !TYPE_ARTIFICIAL (rli->t))
        warning (OPT_Wpadded, "padding struct to align %q+D", field);
 
       /* If the alignment is still within offset_align, just align
@@ -1775,7 +1776,8 @@ finalize_record_size (record_layout_info rli)
 
   if (TREE_CONSTANT (unpadded_size)
       && simple_cst_equal (unpadded_size, TYPE_SIZE (rli->t)) == 0
-      && input_location != BUILTINS_LOCATION)
+      && input_location != BUILTINS_LOCATION
+      && !TYPE_ARTIFICIAL (rli->t))
     warning (OPT_Wpadded, "padding struct size to alignment boundary");
 
   if (warn_packed && TREE_CODE (rli->t) == RECORD_TYPE

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1f3fb60..f3a3b69 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2020-04-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c/94641
+       * c-c++-common/ubsan/pr94641.c: New test.
+
 2020-04-21  Patrick Palka  <ppalka@redhat.com>
 
        PR c++/94597

diff --git a/gcc/testsuite/c-c++-common/ubsan/pr94641.c b/gcc/testsuite/c-c++-common/ubsan/pr94641.c
new file mode 100644 (file)
index 0000000..b41cb06
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/ubsan/pr94641.c
@@ -0,0 +1,11 @@
+/* PR c/94641 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=undefined -Wpadded" } */
+
+void foo (void *) __attribute__((nonnull));
+
+void
+bar (void *p)
+{
+  foo (p);
+}

diff --git a/gcc/ubsan.c b/gcc/ubsan.c
index da93831..acd8a0b 100644 (file)
--- a/gcc/ubsan.c
+++ b/gcc/ubsan.c
@@ -229,6 +229,7 @@ ubsan_get_type_descriptor_type (void)
   TYPE_FIELDS (ret) = fields[0];
   TYPE_NAME (ret) = type_decl;
   TYPE_STUB_DECL (ret) = type_decl;
+  TYPE_ARTIFICIAL (ret) = 1;
   layout_type (ret);
   ubsan_type_descriptor_type = ret;
   return ret;
@@ -277,6 +278,7 @@ ubsan_get_source_location_type (void)
   TYPE_FIELDS (ret) = fields[0];
   TYPE_NAME (ret) = type_decl;
   TYPE_STUB_DECL (ret) = type_decl;
+  TYPE_ARTIFICIAL (ret) = 1;
   layout_type (ret);
   ubsan_source_location_type = ret;
   return ret;
@@ -593,6 +595,7 @@ ubsan_create_data (const char *name, int loccnt, const location_t *ploc, ...)
   TYPE_FIELDS (ret) = fields[0];
   TYPE_NAME (ret) = type_decl;
   TYPE_STUB_DECL (ret) = type_decl;
+  TYPE_ARTIFICIAL (ret) = 1;
   layout_type (ret);
 
   /* Now, fill in the type.  */