[C PATCH] Use warning_at (PR c/60087)

[Marek Polacek]

An obvious one, use location if available.  Can this be considered as
a "docfix" though, thus ok for trunk?  (Not a regression.)

Regtested/bootstrapped on x86_64-linux.

2014-02-06  Marek Polacek  <pola...@redhat.com>

        PR c/60087
c-family/
        * c-common.c (warn_for_sign_compare): Call warning_at with location
        instead of warning.
testsuite/
        * gcc.dg/pr60087.c: New test.

diff --git gcc/c-family/c-common.c gcc/c-family/c-common.c
index 007e727..50cc848 100644
--- gcc/c-family/c-common.c
+++ gcc/c-family/c-common.c
@@ -11285,8 +11285,8 @@ warn_for_sign_compare (location_t location,
               if ((mask & constant) != mask)
                {
                  if (constant == 0)
-                   warning (OPT_Wsign_compare,
-                            "promoted ~unsigned is always non-zero");
+                   warning_at (location, OPT_Wsign_compare,
+                               "promoted ~unsigned is always non-zero");
                  else
                    warning_at (location, OPT_Wsign_compare,
                                "comparison of promoted ~unsigned with 
constant");
diff --git gcc/testsuite/gcc.dg/pr60087.c gcc/testsuite/gcc.dg/pr60087.c
index e69de29..9cdd589 100644
--- gcc/testsuite/gcc.dg/pr60087.c
+++ gcc/testsuite/gcc.dg/pr60087.c
@@ -0,0 +1,14 @@
+/* PR c/60087 */
+/* { dg-do compile } */
+/* { dg-options "-Wsign-compare" } */
+
+void
+foo (unsigned int ui, int i)
+{
+  const unsigned char uc = 0;
+  _Bool b;
+  b = 0 != ~uc; /* { dg-warning "9:promoted ~unsigned is always non-zero" } */
+  b = 2 != ~uc; /* { dg-warning "9:comparison of promoted ~unsigned with 
constant" } */
+  b = uc == ~uc; /* { dg-warning "10:comparison of promoted ~unsigned with 
unsigned" } */
+  b = i == ui; /* { dg-warning "9:comparison between signed and unsigned 
integer expressions" } */
+}

        Marek