gcc/

2010-04-27  Shujing Zhao  <pearly.zhao@oracle.com>

        PR c/32207
        * c-typeck.c (build_binary_op): Move forward check for comparison
        pointer with null pointer constant and adjust the diagnostic message.

gcc/testsuite/
2010-04-27  Shujing Zhao  <pearly.zhao@oracle.com>

        PR c/32207
        * gcc.dg/pr32207.c: New test.
        * gcc.dg/misc-column.c: Adjust expected warning.
        * gcc.dg/Walways-true-1.c: Likewise.
        * gcc.dg/Walways-true-2.c: Likewise.
        * gcc.dg/warn-addr-cmp.c: Likewise.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@158765 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 30 insertions, 21 deletions

diff --git a/gcc/testsuite/gcc.dg/Walways-true-1.c b/gcc/testsuite/gcc.dg/Walways-true-1.c
index 32b921c3fa7..274ec32b38b 100644
--- a/gcc/testsuite/gcc.dg/Walways-true-1.c
+++ b/gcc/testsuite/gcc.dg/Walways-true-1.c
@@ -26,32 +26,32 @@ bar (int a)
     foo (5);
   if (&&lab)	/* { dg-warning "7:always evaluate as" "correct warning" } */
     foo (6);
-  if (foo == 0)	/* { dg-warning "11:never be NULL" "correct warning" } */
+  if (foo == 0)	/* { dg-warning "11:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (7);
   if (foo (1) == 0)
     foo (8);
-  if (&i == 0)	/* { dg-warning "10:never be NULL" "correct warning" } */
+  if (&i == 0)	/* { dg-warning "10:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (9);
   if (i == 0)
     foo (10);
-  if (&a == 0)	/* { dg-warning "10:never be NULL" "correct warning" } */
+  if (&a == 0)	/* { dg-warning "10:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (11);
   if (a == 0)
     foo (12);
-  if (&&lab == 0) /* { dg-warning "13:never be NULL" "correct warning" } */
+  if (&&lab == 0) /* { dg-warning "13:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (13);
-  if (0 == foo)	/* { dg-warning "9:never be NULL" "correct warning" } */
+  if (0 == foo)	/* { dg-warning "9:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (14);
   if (0 == foo (1))
     foo (15);
-  if (0 == &i)	/* { dg-warning "9:never be NULL" "correct warning" } */
+  if (0 == &i)	/* { dg-warning "9:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (16);
   if (0 == i)
     foo (17);
-  if (0 == &a)	/* { dg-warning "9:never be NULL" "correct warning" } */
+  if (0 == &a)	/* { dg-warning "9:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (18);
   if (0 == a)
     foo (19);
-  if (0 == &&lab) /* { dg-warning "9:never be NULL" "correct warning" } */
+  if (0 == &&lab) /* { dg-warning "9:the comparison will always evaluate to 'false'" "correct warning" } */
     foo (20);
 }
diff --git a/gcc/testsuite/gcc.dg/Walways-true-2.c b/gcc/testsuite/gcc.dg/Walways-true-2.c
index c14857eaee6..3978a446188 100644
--- a/gcc/testsuite/gcc.dg/Walways-true-2.c
+++ b/gcc/testsuite/gcc.dg/Walways-true-2.c
@@ -37,11 +37,11 @@ bar (int a)
     foo (9);
   if (i == 0)
     foo (10);
-  if (&a == 0)	/* { dg-warning "never be NULL" "correct warning" } */
+  if (&a == 0)	/* { dg-warning "the comparison will always evaluate to 'false'" "correct warning" } */
     foo (11);
   if (a == 0)
     foo (12);
-  if (&&lab == 0) /* { dg-warning "never be NULL" "correct warning" } */
+  if (&&lab == 0) /* { dg-warning "the comparison will always evaluate to 'false'" "correct warning" } */
     foo (13);
   if (0 == foo)
     foo (14);
@@ -51,10 +51,10 @@ bar (int a)
     foo (16);
   if (0 == i)
     foo (17);
-  if (0 == &a)	/* { dg-warning "never be NULL" "correct warning" } */
+  if (0 == &a)	/* { dg-warning "the comparison will always evaluate to 'false'" "correct warning" } */
     foo (18);
   if (0 == a)
     foo (19);
-  if (0 == &&lab) /* { dg-warning "never be NULL" "correct warning" } */
+  if (0 == &&lab) /* { dg-warning "the comparison will always evaluate to 'false'" "correct warning" } */
     foo (20);
 }
diff --git a/gcc/testsuite/gcc.dg/misc-column.c b/gcc/testsuite/gcc.dg/misc-column.c
index a24427e4baa..f69f98884d9 100644
--- a/gcc/testsuite/gcc.dg/misc-column.c
+++ b/gcc/testsuite/gcc.dg/misc-column.c
@@ -19,7 +19,7 @@ void foo (void)
   if (p < q) /* { dg-warning "9:comparison of distinct pointer types" } */
     bar ();
 
-  if (&p == 0) /* { dg-warning "10:will never be NULL" } */
+  if (&p == 0) /* { dg-warning "10:comparison will always evaluate to 'false'" } */
     bar();
 
   if (p == 4) /* { dg-warning "9:comparison between pointer and integer" } */
diff --git a/gcc/testsuite/gcc.dg/pr32207.c b/gcc/testsuite/gcc.dg/pr32207.c
new file mode 100644
index 00000000000..549d51a9e9d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr32207.c
@@ -0,0 +1,9 @@
+/* Test warning for comparison non-null address with null pointer constant. */
+/* Origin: Pawel Sikora <pluto@agmk.net> */
+/* { dg-do compile } */
+/* { dg-options "-Waddress" } */
+extern void z();
+
+void f() { if ( z ) z(); } /* { dg-warning "always evaluate as" } */
+void g() { if ( z != 0 ) z(); } /* { dg-warning "the comparison will always evaluate to 'true'" } */
+void h() { if ( z != (void*)0 ) z(); } /* { dg-warning "the comparison will always evaluate to 'true'" } */
diff --git a/gcc/testsuite/gcc.dg/warn-addr-cmp.c b/gcc/testsuite/gcc.dg/warn-addr-cmp.c
index 6ad94731aff..c1e68f5c598 100644
--- a/gcc/testsuite/gcc.dg/warn-addr-cmp.c
+++ b/gcc/testsuite/gcc.dg/warn-addr-cmp.c
@@ -36,13 +36,13 @@ test_func_cmp (void)
 int
 test_func_cmp_rhs_zero (void)
 {
-  if (func == 0)     /* { dg-warning "the address of 'func'" } */
+  if (func == 0)     /* { dg-warning "the comparison will always evaluate to 'false'" } */
     return 1;
-  if (func != 0)     /* { dg-warning "the address of 'func'" } */
+  if (func != 0)     /* { dg-warning "the comparison will always evaluate to 'true'" } */
     return 1;
-  if (&var == 0)     /* { dg-warning "the address of 'var'" } */
+  if (&var == 0)     /* { dg-warning "the comparison will always evaluate to 'false'" } */
     return 1;
-  if (&var != 0)     /* { dg-warning "the address of 'var'" } */
+  if (&var != 0)     /* { dg-warning "the comparison will always evaluate to 'true'" } */
     return 1;
   if (weak_func == 0)
     return 1;
@@ -59,13 +59,13 @@ test_func_cmp_rhs_zero (void)
 int
 test_func_cmp_lhs_zero (void)
 {
-  if (0 == func)     /* { dg-warning "the address of 'func'" } */
+  if (0 == func)     /* { dg-warning "the comparison will always evaluate to 'false'" } */
     return 1;
-  if (0 != func)     /* { dg-warning "the address of 'func'" } */
+  if (0 != func)     /* { dg-warning "the comparison will always evaluate to 'true'" } */
     return 1;
-  if (0 == &var)     /* { dg-warning "the address of 'var'" } */
+  if (0 == &var)     /* { dg-warning "the comparison will always evaluate to 'false'" } */
     return 1;
-  if (0 != &var)     /* { dg-warning "the address of 'var'" } */
+  if (0 != &var)     /* { dg-warning "the comparison will always evaluate to 'true'" } */
     return 1;
   if (0 == weak_func)
     return 1;