Guard notes for -Waddress-of-packed-member on warning emission (PR c/89985)

gcc/c-family/ChangeLog:
	PR c/89985
	* c-warn.c (check_address_or_pointer_of_packed_member): Add
	auto_diagnostic_group.  Guard inform calls by result of
	warning_at call.

gcc/testsuite/ChangeLog:
	PR c/89985
	* c-c++-common/pr89985.c: New test.

From-SVN: r270169

diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 5cce5de..f941403 100644 (file)
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,10 @@
+2019-04-05  David Malcolm  <dmalcolm@redhat.com>
+
+       PR c/89985
+       * c-warn.c (check_address_or_pointer_of_packed_member): Add
+       auto_diagnostic_group.  Guard inform calls by result of
+       warning_at call.
+
 2019-04-05  Marek Polacek  <polacek@redhat.com>
 
        PR c++/89973 - -Waddress-of-packed-member ICE with invalid conversion. 

diff --git a/gcc/c-family/c-warn.c b/gcc/c-family/c-warn.c
index 05ea2bf..f6acc67 100644 (file)
--- a/gcc/c-family/c-warn.c
+++ b/gcc/c-family/c-warn.c
@@ -2783,18 +2783,21 @@ check_address_or_pointer_of_packed_member (tree type, tree rhs)
          unsigned int rhs_align = min_align_of_type (rhstype);
          if (rhs_align < type_align)
            {
+             auto_diagnostic_group d;
              location_t location = EXPR_LOC_OR_LOC (rhs, input_location);
-             warning_at (location, OPT_Waddress_of_packed_member,
-                         "converting a packed %qT pointer (alignment %d) "
-                         "to a %qT pointer (alignment %d) may result in an "
-                         "unaligned pointer value",
-                         rhstype, rhs_align, type, type_align);
-             tree decl = TYPE_STUB_DECL (rhstype);
-             if (decl)
-               inform (DECL_SOURCE_LOCATION (decl), "defined here");
-             decl = TYPE_STUB_DECL (type);
-             if (decl)
-               inform (DECL_SOURCE_LOCATION (decl), "defined here");
+             if (warning_at (location, OPT_Waddress_of_packed_member,
+                             "converting a packed %qT pointer (alignment %d) "
+                             "to a %qT pointer (alignment %d) may result in "
+                             "an unaligned pointer value",
+                             rhstype, rhs_align, type, type_align))
+               {
+                 tree decl = TYPE_STUB_DECL (rhstype);
+                 if (decl)
+                   inform (DECL_SOURCE_LOCATION (decl), "defined here");
+                 decl = TYPE_STUB_DECL (type);
+                 if (decl)
+                   inform (DECL_SOURCE_LOCATION (decl), "defined here");
+               }
            }
        }
       return NULL_TREE;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c188628..83fccaa 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-04-05  David Malcolm  <dmalcolm@redhat.com>
+
+       PR c/89985
+       * c-c++-common/pr89985.c: New test.
+
 2019-04-05  Christophe Lyon  <christophe.lyon@linaro.org>
 
        PR c/71598

diff --git a/gcc/testsuite/c-c++-common/pr89985.c b/gcc/testsuite/c-c++-common/pr89985.c
new file mode 100644 (file)
index 0000000..82a7285
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/pr89985.c
@@ -0,0 +1,19 @@
+/* Ensure that -Waddress-of-packed-member doesn't emit notes when
+   suppressed via -w, rather than -Wno-address-of-packed-member.  */
+
+/* { dg-do compile } */
+/* { dg-options "-w" } */
+
+struct a { /* { dg-bogus "defined here" } */
+  void *ptr;
+} __attribute__((packed));
+
+struct b { /* { dg-bogus "defined here" } */
+  void *ptr;
+};
+
+void
+test (struct a *p)
+{
+  struct b *q = (struct b *)p;
+}