gcc/

2010-05-07  Shujing Zhao  <pearly.zhao@oracle.com>

        * c-typeck.c (build_binary_op): Warn ordered comparison of pointer
        with null pointer and also warn about ordered comparison of zero
        with pointer if -Wextra.

gcc/testsuite/
2010-05-07  Shujing Zhao  <pearly.zhao@oracle.com>

        * gcc.dg/ordered-comparison-1.c: New test.
        * gcc.dg/ordered-comparison-2.c: New test.
        * gcc.dg/ordered-comparison-3.c: New test.
        * gcc.dg/ordered-comparison-4.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@159145 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5839779cb8ed45cf9de020a6d600d33c12869e3f..f1885a9d82915cfed08f1f5c223636aeb2f01d9b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-05-07  Shujing Zhao  <pearly.zhao@oracle.com>
+
+       * c-typeck.c (build_binary_op): Warn ordered comparison of pointer
+       with null pointer and also warn about ordered comparison of zero with
+       pointer if -Wextra.
+
 2010-05-05  Andreas Simbuerger  <simbuerg@fim.uni-passau.de>
 
        * graphite-blocking.c

diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index 96b2ab156ad0782b6028e4021ac866d099dc4a6a..2f66d6a1446bd72f6f3cb93291bce2b8c2f11f80 100644 (file)
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -9625,6 +9625,11 @@ build_binary_op (location_t location, enum tree_code code,
              else if (TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
                pedwarn (location, OPT_pedantic, "ISO C forbids "
                         "ordered comparisons of pointers to functions");
+             else if (null_pointer_constant_p (orig_op0)
+                      || null_pointer_constant_p (orig_op1))
+               warning_at (location, OPT_Wextra,
+                           "ordered comparison of pointer with null pointer");
+
            }
          else if (!addr_space_superset (as0, as1, &as_common))
            {
@@ -9649,13 +9654,17 @@ build_binary_op (location_t location, enum tree_code code,
                     "ordered comparison of pointer with integer zero");
          else if (extra_warnings)
            warning_at (location, OPT_Wextra,
-                    "ordered comparison of pointer with integer zero");
+                       "ordered comparison of pointer with integer zero");
        }
       else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
        {
          result_type = type1;
-         pedwarn (location, OPT_pedantic,
-                  "ordered comparison of pointer with integer zero");
+         if (pedantic)
+           pedwarn (location, OPT_pedantic,
+                    "ordered comparison of pointer with integer zero");
+         else if (extra_warnings)
+           warning_at (location, OPT_Wextra,
+                       "ordered comparison of pointer with integer zero");
        }
       else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
        {

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1377bcbec0dd8fd05f6ffbcd821cab59a93619b4..50397eff888afe3508821ea2133eb4786e3726d6 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2010-05-07  Shujing Zhao  <pearly.zhao@oracle.com>
+
+       * gcc.dg/ordered-comparison-1.c: New test.
+       * gcc.dg/ordered-comparison-2.c: New test.
+       * gcc.dg/ordered-comparison-3.c: New test.
+       * gcc.dg/ordered-comparison-4.c: New test.
+
 2010-05-06  Mike Stump  <mikestump@comcast.net>
 
        PR objc/35165

diff --git a/gcc/testsuite/gcc.dg/ordered-comparison-1.c b/gcc/testsuite/gcc.dg/ordered-comparison-1.c
new file mode 100644 (file)
index 0000000..0131c9d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ordered-comparison-1.c
@@ -0,0 +1,21 @@
+/* Test warning for ordered comparison pointer with null pointer constant. */
+/* Tested with no warning option. */
+/* { dg-do compile } */
+/* { dg-options "" } */
+extern void z();
+void *p;
+
+void f() {
+ if (z >= 0)
+   z();
+ if (0 >= z)
+    z();
+ if (p >= (void*)0)
+    z();
+ if ((void*)0 >= p)
+    z();
+ if (z >= (void*)0) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+ if ((void*)0 >=z) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+}

diff --git a/gcc/testsuite/gcc.dg/ordered-comparison-2.c b/gcc/testsuite/gcc.dg/ordered-comparison-2.c
new file mode 100644 (file)
index 0000000..a99d9c3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ordered-comparison-2.c
@@ -0,0 +1,21 @@
+/* Test warning for ordered comparison pointer with null pointer constant. */
+/* Tested with -pedantic. */
+/* { dg-do compile } */
+/* { dg-options "-pedantic" } */
+extern void z();
+void *p;
+
+void f() {
+ if (z >= 0) /* { dg-warning "ordered comparison of pointer with" } */
+   z();
+ if (0 >= z) /* { dg-warning "ordered comparison of pointer with" } */
+    z();
+ if (p >= (void*)0)
+    z();
+ if ((void*)0 >= p)
+    z();
+ if (z >= (void*)0) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+ if ((void*)0 >=z) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+}

diff --git a/gcc/testsuite/gcc.dg/ordered-comparison-3.c b/gcc/testsuite/gcc.dg/ordered-comparison-3.c
new file mode 100644 (file)
index 0000000..2e4be49
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ordered-comparison-3.c
@@ -0,0 +1,21 @@
+/* Test warning for ordered comparison pointer with null pointer constant. */
+/* Test with -pedantic-errors. */
+/* { dg-do compile } */
+/* { dg-options "-pedantic-errors" } */
+extern void z();
+void *p;
+
+void f() {
+ if ( z >= 0 ) /* { dg-error "ordered comparison of pointer with" } */
+   z();
+ if ( 0 >= z) /* { dg-error "ordered comparison of pointer with" } */
+    z();
+ if ( p >= (void*)0 )
+    z();
+ if ( (void*)0 >= p)
+    z();
+ if (z >= (void*)0) /* { dg-error "distinct pointer types lacks a cast" } */
+    z();
+ if ((void*)0 >=z) /* { dg-error "distinct pointer types lacks a cast" } */
+    z(); 
+}

diff --git a/gcc/testsuite/gcc.dg/ordered-comparison-4.c b/gcc/testsuite/gcc.dg/ordered-comparison-4.c
new file mode 100644 (file)
index 0000000..ebe9edd
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ordered-comparison-4.c
@@ -0,0 +1,21 @@
+/* Test warning for ordered comparison pointer with null pointer constant. */
+/* Test with -Wextra. */
+/* { dg-do compile } */
+/* { dg-options "-Wextra" } */
+extern void z();
+void *p;
+
+void f() {
+ if (z >= 0) /* { dg-warning "ordered comparison of pointer with" } */
+   z();
+ if (0 >= z) /* { dg-warning "ordered comparison of pointer with" } */
+    z();
+ if (p >= (void*)0) /* { dg-warning "ordered comparison of pointer with null pointer" } */
+    z();
+ if ((void*)0 >= p) /* { dg-warning "ordered comparison of pointer with null pointer" } */
+    z();
+ if (z >= (void*)0) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+ if ((void*)0 >=z) /* { dg-warning "distinct pointer types lacks a cast" } */
+    z();
+}