[PATCH] Typo in mapwms.c (and lots of warnings)

[Petter Reinholdtsen]

I recently started looking at the mapserver source, and discovered
that it is compiled using very few warning flags enabled.  When
enabling more warnings, I found several bugs.  This is about one of
them.  I use this patch to enable more warnings:

Index: aclocal.m4
===================================================================
RCS file: /data2/cvsroot/mapserver/aclocal.m4,v
retrieving revision 1.10
diff -u -r1.10 aclocal.m4
--- aclocal.m4  22 Jul 2003 20:05:25 -0000      1.10
+++ aclocal.m4  24 Jan 2005 08:37:21 -0000
@@ -33,20 +33,21 @@

 AC_DEFUN(AC_COMPILER_WFLAGS,
 [
+       WFLAGS="-W -Wall -Wcast-align -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wpointer-arith -Wreturn-type"
        # Remove -g from compile flags, we will add via CFG variable if
        # we need it.
        CXXFLAGS=`echo "$CXXFLAGS " | sed "s/-g //"`
        CFLAGS=`echo "$CFLAGS " | sed "s/-g //"`

-       # check for GNU compiler, and use -Wall
+       # check for GNU compiler, and use warning flags
        if test "$GCC" = "yes"; then
-               C_WFLAGS="-Wall"
-               CFLAGS="$CFLAGS -Wall"
+               C_WFLAGS="$WFLAGS"
+               CFLAGS="$CFLAGS $WFLAGS"
                AC_DEFINE(USE_GNUCC)
        fi
        if test "$GXX" = "yes"; then
-               CXX_WFLAGS="-Wall"
-               CXXFLAGS="$CXXFLAGS -Wall"
+               CXX_WFLAGS="$WFLAGS"
+               CXXFLAGS="$CXXFLAGS $WFLAGS"
                AC_DEFINE(USE_GNUCC)
        fi
        AC_SUBST(CXX_WFLAGS,$CXX_WFLAGS)
@@ -55,16 +56,17 @@

 AC_DEFUN(AC_COMPILER_WFLAGS_DEBUG,
 [
+       WFLAGS="-W -Wall -Wcast-align -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wpointer-arith -Wreturn-type"
        # -g should already be in compile flags.
-       # check for GNU compiler, and add -Wall
+       # check for GNU compiler, and add warning flags
        if test "$GCC" = "yes"; then
-               C_WFLAGS="-Wall"
-               CFLAGS="$CFLAGS -Wall"
+               C_WFLAGS="$WFLAGS"
+               CFLAGS="$CFLAGS $WFLAGS"
                AC_DEFINE(USE_GNUCC)
        fi
        if test "$GXX" = "yes"; then
-               CXX_WFLAGS="-Wall"
-               CXXFLAGS="$CXXFLAGS -Wall"
+               CXX_WFLAGS="$WFLAGS"
+               CXXFLAGS="$CXXFLAGS $WFLAGS"
                AC_DEFINE(USE_GNUCC)
        fi
        AC_SUBST(CXX_WFLAGS,$CXX_WFLAGS)

This in turn report lots and lots of potential problems in the code.
I would like to help getting rid of all these warnings, but will need
commends and suggestions on how to best solve them.

One of the warnings are this one.

  mapwms.c:1959: warning: ordered comparison of pointer with integer zero

The problem seem to be a missing index in the source, where the
pointer to an array is compared with zero instead of the value in the
array.  This patch solve the problem.  Please include it in a future
version of mapserver.

Index: mapwms.c
===================================================================
RCS file: /data2/cvsroot/mapserver/mapwms.c,v
retrieving revision 1.158
diff -u -r1.158 mapwms.c
--- mapwms.c    14 Jan 2005 05:03:01 -0000      1.158
+++ mapwms.c    24 Jan 2005 08:38:46 -0000
@@ -1955,7 +1958,7 @@
      //free the stuff used for nested layers
      for (i = 0; i < map->numlayers; i++)
      {
-       if (numNestedGroups > 0)
+       if (numNestedGroups[i] > 0)
        {
          msFreeCharArray(nestedGroups[i], numNestedGroups[i]);
        }