[PATCH 5/7] build: add more compiler checking

[Eric Blake]

Enable a bit more gcc warning coverage.

* configure.ac (nw): Turn on some warnings that no longer trigger
a gcc warning, or where we reduce the scope of unwarned code.
* src/m4.h (progname): Drop redundant declaration.
* src/builtin.c (includes): Use header for program_name.

Signed-off-by: Eric Blake <address@hidden>
---
 ChangeLog     |  6 ++++++
 configure.ac  | 10 ++++------
 src/builtin.c |  1 +
 src/m4.h      |  1 -
 4 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index bc01374..35f0748 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2012-09-04  Eric Blake  <address@hidden>

+       build: add more compiler checking
+       * configure.ac (nw): Turn on some warnings that no longer trigger
+       a gcc warning, or where we reduce the scope of unwarned code.
+       * src/m4.h (progname): Drop redundant declaration.
+       * src/builtin.c (includes): Use header for program_name.
+
        build: pick up latest gnulib fixes
        * gnulib: Update to latest.
        * m4/gnulib-cache.m4: Regenerate.
diff --git a/configure.ac b/configure.ac
index cedb922..6886273 100644
--- a/configure.ac
+++ b/configure.ac
@@ -72,17 +72,15 @@ if test "$gl_gcc_warnings" = yes; then
     CFLAGS=$save_CFLAGS])

   nw=
-  nw="$nw -Waggregate-return"       # C90 is anachronistic
+  nw="$nw -Waggregate-return"       # K&R is anachronistic
+  nw="$nw -Wtraditional-conversion" # K&R is anachronistic
+  nw="$nw -Wundef"                  # K&R is anachronistic
+  nw="$nw -Wtraditional"            # K&R is anachronistic
   nw="$nw -Wlong-long"              # C90 is anachronistic
-  nw="$nw -Wundef"                  # Warns on '#if GNULIB_FOO' etc in gnulib
-  nw="$nw -Wtraditional"            # Warns on #elif which we use often
   nw="$nw -Wsystem-headers"         # Don't let system headers trigger warnings
   nw="$nw -Wpadded"                 # Our structs are not packed
-  nw="$nw -Wredundant-decls"        # Gnulib has multiple decls
-  nw="$nw -Wunreachable-code"       # Needed in output.c
   nw="$nw -Wconversion"             # Too many warnings for now
   nw="$nw -Wsign-conversion"        # Too many warnings for now
-  nw="$nw -Wtraditional-conversion" # Too many warnings for now
   nw="$nw -Wcast-qual"              # Too many warnings for now
   nw="$nw -Wswitch-enum"            # Too many warnings for now
   # This, $nw, is the list of warnings we disable.
diff --git a/src/builtin.c b/src/builtin.c
index 5ff443e..b7e4e11 100644
--- a/src/builtin.c
+++ b/src/builtin.c
@@ -26,6 +26,7 @@

 #include "execute.h"
 #include "memchr2.h"
+#include "progname.h"
 #include "regex.h"
 #include "spawn-pipe.h"
 #include "wait-process.h"
diff --git a/src/m4.h b/src/m4.h
index c23e448..8ddb9da 100644
--- a/src/m4.h
+++ b/src/m4.h
@@ -138,7 +138,6 @@ extern const char *user_word_regexp;    /* -W */

 /* Error handling.  */
 extern int retcode;
-extern const char *program_name;

 void m4_error (int, int, const char *, ...) M4_GNUC_PRINTF(3, 4);
 void m4_error_at_line (int, int, const char *, int,
-- 
1.7.11.4