[Emacs-diffs] /srv/bzr/emacs/trunk r112631: Port --enable-gcc-warnings to clang.

[Paul Eggert]

------------------------------------------------------------
revno: 112631
committer: Paul Eggert <address@hidden>
branch nick: trunk
timestamp: Fri 2013-05-17 22:32:17 -0700
message:
  Port --enable-gcc-warnings to clang.
  
  * configure.ac (nw): Remove obsolescent warnings.
  These aren't needed for clang, or for gcc for that matter.
  (emacs_cv_clang): New var, which tests for clang.
  Omit warnings that clang is too picky about.
  (GLIB_DISABLE_DEPRECATION_WARNINGS): Define this;
  needed for Ubuntu 13.04 + clang + --enable-gcc-warnings.
  * lib-src/etags.c: Omit unnecessary forward decls.
  (print_version, print_help): Declare _Noreturn.
  * lib-src/pop.c (socket_connection) [HAVE_GETADDRINFO]: Simplify.
  * src/bytecode.c (exec_byte_code):
  * src/regex.c:
  Redo diagnostic pragmas to pacify clang, too.
  * src/dbusbind.c (xd_retrieve_arg): Do not use uninitialized variable.
  * src/editfns.c (Fencode_time):
  * src/fileio.c (file_accessible_directory_p):
  * src/font.c (font_unparse_xlfd):
  Use '&"string"[index]' instead of '"string" + (index)'.
  * src/undo.c (user_error): Remove; unused.
modified:
  ChangeLog
  configure.ac
  lib-src/ChangeLog
  lib-src/etags.c
  lib-src/pop.c
  src/ChangeLog
  src/bytecode.c
  src/dbusbind.c
  src/editfns.c
  src/fileio.c
  src/font.c
  src/regex.c
  src/undo.c

=== modified file 'ChangeLog'
--- a/ChangeLog 2013-05-18 05:21:24 +0000
+++ b/ChangeLog 2013-05-18 05:32:17 +0000
@@ -1,5 +1,13 @@
 2013-05-18  Paul Eggert  <address@hidden>
 
+       Port --enable-gcc-warnings to clang.
+       * configure.ac (nw): Remove obsolescent warnings.
+       These aren't needed for clang, or for gcc for that matter.
+       (emacs_cv_clang): New var, which tests for clang.
+       Omit warnings that clang is too picky about.
+       (GLIB_DISABLE_DEPRECATION_WARNINGS): Define this;
+       needed for Ubuntu 13.04 + clang + --enable-gcc-warnings.
+
        * make-dist (files): Add nt/Makefile.in, nt/gnulib.mk.
        Otherwise, 'configure; make' fails on non-Windows builds.
 

=== modified file 'configure.ac'
--- a/configure.ac      2013-05-15 16:15:07 +0000
+++ b/configure.ac      2013-05-18 05:32:17 +0000
@@ -554,7 +554,7 @@
   i[3456]86-*-* )
     case "${canonical}" in
       *-darwin* )               opsys=darwin ;;
-      *-mingw32 )              
+      *-mingw32 )
                opsys=mingw32
                # MinGW overrides and adds some system headers in nt/inc.
                GCC_TEST_OPTIONS="-I $srcdir/nt/inc"
@@ -747,27 +747,13 @@
   esac
   AC_SUBST([WERROR_CFLAGS])
 
-  nw="$nw -Waggregate-return"       # anachronistic
-  nw="$nw -Wlong-long"              # C90 is anachronistic
-  nw="$nw -Wc++-compat"             # We don't care about C++ compilers
-  nw="$nw -Wundef"                  # Warns on '#if GNULIB_FOO' etc in gnulib
-  nw="$nw -Wtraditional"            # Warns on #elif which we use often
-  nw="$nw -Wcast-qual"              # Too many warnings for now
-  nw="$nw -Wconversion"             # Too many warnings for now
   nw="$nw -Wsystem-headers"         # Don't let system headers trigger warnings
-  nw="$nw -Wsign-conversion"        # Too many warnings for now
   nw="$nw -Woverlength-strings"     # Not a problem these days
-  nw="$nw -Wtraditional-conversion" # Too many warnings for now
-  nw="$nw -Wunreachable-code"       # so buggy that it's now silently ignored
-  nw="$nw -Wpadded"                 # Our structs are not padded
-  nw="$nw -Wredundant-decls"        # we regularly (re)declare functions
   nw="$nw -Wlogical-op"             # any use of fwrite provokes this
   nw="$nw -Wformat-nonliteral"      # we do this a lot
   nw="$nw -Wvla"                    # warnings in gettext.h
   nw="$nw -Wnested-externs"         # use of XARGMATCH/verify_function__
-  nw="$nw -Wswitch-enum"            # Too many warnings for now
   nw="$nw -Wswitch-default"         # Too many warnings for now
-  nw="$nw -Wfloat-equal"            # warns about high-quality code
   nw="$nw -Winline"                 # OK to ignore 'inline'
   nw="$nw -Wjump-misses-init"       # We sometimes safely jump over init.
   nw="$nw -Wstrict-overflow"        # OK to optimize assuming that
@@ -785,6 +771,20 @@
   # The following line should be removable at some point.
   nw="$nw -Wsuggest-attribute=pure"
 
+  # clang is unduly picky about some things.
+  AC_CACHE_CHECK([whether the compiler is clang], [emacs_cv_clang],
+    [AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM([[
+           #ifndef __clang__
+             #error "not clang"
+           #endif
+          ]])],
+       [emacs_cv_clang=yes],
+       [emacs_cv_clang=no])])
+  if test $emacs_cv_clang = yes; then
+    nw="$nw -Wcast-align"
+  fi
+
   gl_MANYWARN_ALL_GCC([ws])
   gl_MANYWARN_COMPLEMENT([ws], [$ws], [$nw])
   for w in $ws; do
@@ -801,6 +801,14 @@
   # gcc 4.5.0 20090517.
   gl_WARN_ADD([-Wno-logical-op])
 
+  # More things that clang is unduly picky about.
+  if test $emacs_cv_clang = yes; then
+    gl_WARN_ADD([-Wno-format-extra-args])
+    gl_WARN_ADD([-Wno-tautological-constant-out-of-range-compare])
+    gl_WARN_ADD([-Wno-unused-command-line-argument])
+    gl_WARN_ADD([-Wno-unused-value])
+  fi
+
   gl_WARN_ADD([-fdiagnostics-show-option])
   gl_WARN_ADD([-funit-at-a-time])
 
@@ -1604,15 +1612,15 @@
 EMACS_MANIFEST=
 if test "${with_w32}" != no; then
   case "${opsys}" in
-    cygwin) 
+    cygwin)
       AC_CHECK_HEADER([windows.h], [HAVE_W32=yes],
              [AC_MSG_ERROR([`--with-w32' was specified, but windows.h
-                   cannot be found.])]) 
+                   cannot be found.])])
     ;;
     mingw32)
     ## Using --with-w32 with MinGW is a no-op, but we allow it.
     ;;
-    *) 
+    *)
       AC_MSG_ERROR([Using w32 with an autotools build is only supported for 
Cygwin and MinGW32.])
     ;;
   esac
@@ -1626,7 +1634,7 @@
    [[void test(PIMAGE_NT_HEADERS pHeader)
      {PIMAGE_SECTION_HEADER pSection = IMAGE_FIRST_SECTION(pHeader);}]])],
    [emacs_cv_w32api=yes
-    HAVE_W32=yes], 
+    HAVE_W32=yes],
    emacs_cv_w32api=no)
   AC_MSG_RESULT($emacs_cv_w32api)
   if test "${emacs_cv_w32api}" = "no"; then
@@ -2074,6 +2082,7 @@
        USE_GTK_TOOLKIT="GTK3"
        if test "x$ac_enable_gtk_deprecation_warnings" = x; then
                  GTK_CFLAGS="$GTK_CFLAGS -DGDK_DISABLE_DEPRECATION_WARNINGS"
+                 GTK_CFLAGS="$GTK_CFLAGS -DGLIB_DISABLE_DEPRECATION_WARNINGS"
        fi
     else
        check_gtk2=yes

=== modified file 'lib-src/ChangeLog'
--- a/lib-src/ChangeLog 2013-05-16 12:48:54 +0000
+++ b/lib-src/ChangeLog 2013-05-18 05:32:17 +0000
@@ -1,3 +1,10 @@
+2013-05-18  Paul Eggert  <address@hidden>
+
+       Port --enable-gcc-warnings to clang.
+       * etags.c: Omit unnecessary forward decls.
+       (print_version, print_help): Declare _Noreturn.
+       * pop.c (socket_connection) [HAVE_GETADDRINFO]: Simplify.
+
 2013-05-16  Eli Zaretskii  <address@hidden>
 
        * update-game-score.c [WINDOWSNT]: Include "ntlib.h".

=== modified file 'lib-src/etags.c'
--- a/lib-src/etags.c   2013-03-13 07:27:34 +0000
+++ b/lib-src/etags.c   2013-05-18 05:32:17 +0000
@@ -316,15 +316,7 @@
 static void Yacc_entries (FILE *);
 static void just_read_file (FILE *);
 
-static void print_language_names (void);
-static void print_version (void);
-static void print_help (argument *);
-int main (int, char **);
-
-static compressor *get_compressor_from_suffix (char *, char **);
 static language *get_language_from_langname (const char *);
-static language *get_language_from_interpreter (char *);
-static language *get_language_from_filename (char *, bool);
 static void readline (linebuffer *, FILE *);
 static long readline_internal (linebuffer *, FILE *);
 static bool nocase_tail (const char *);
@@ -346,7 +338,6 @@
 static void free_tree (node *);
 static void free_fdesc (fdesc *);
 static void pfnote (char *, bool, char *, int, int, long);
-static void make_tag (const char *, int, bool, char *, int, int, long);
 static void invalidate_nodes (fdesc *, node **);
 static void put_entries (node *);
 
@@ -816,7 +807,7 @@
 #ifndef VERSION
 # define VERSION "17.38.1.4"
 #endif
-static void
+static _Noreturn void
 print_version (void)
 {
   char emacs_copyright[] = COPYRIGHT;
@@ -832,7 +823,7 @@
 # define PRINT_UNDOCUMENTED_OPTIONS_HELP FALSE
 #endif
 
-static void
+static _Noreturn void
 print_help (argument *argbuffer)
 {
   bool help_for_lang = FALSE;

=== modified file 'lib-src/pop.c'
--- a/lib-src/pop.c     2013-03-12 22:00:07 +0000
+++ b/lib-src/pop.c     2013-05-18 05:32:17 +0000
@@ -1075,28 +1075,22 @@
        }
     } while (ret != 0);
 
-  if (ret == 0)
+  for (it = res; it; it = it->ai_next)
+    if (it->ai_addrlen == sizeof addr)
+      {
+       struct sockaddr_in *in_a = (struct sockaddr_in *) it->ai_addr;
+       addr.sin_addr = in_a->sin_addr;
+       if (! connect (sock, (struct sockaddr *) &addr, sizeof addr))
+         break;
+      }
+  connect_ok = it != NULL;
+  if (connect_ok)
     {
-      it = res;
-      while (it)
-        {
-          if (it->ai_addrlen == sizeof (addr))
-            {
-              struct sockaddr_in *in_a = (struct sockaddr_in *) it->ai_addr;
-              addr.sin_addr = in_a->sin_addr;
-              if (! connect (sock, (struct sockaddr *) &addr, sizeof (addr)))
-                break;
-            }
-          it = it->ai_next;
-        }
-      connect_ok = it != NULL;
-      if (connect_ok)
-        {
-          realhost = alloca (strlen (it->ai_canonname) + 1);
-          strcpy (realhost, it->ai_canonname);
-        }
-      freeaddrinfo (res);
+      realhost = alloca (strlen (it->ai_canonname) + 1);
+      strcpy (realhost, it->ai_canonname);
     }
+  freeaddrinfo (res);
+
 #else /* !HAVE_GETADDRINFO */
   do
     {

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-05-16 19:15:32 +0000
+++ b/src/ChangeLog     2013-05-18 05:32:17 +0000
@@ -1,3 +1,16 @@
+2013-05-18  Paul Eggert  <address@hidden>
+
+       Port --enable-gcc-warnings to clang.
+       * bytecode.c (exec_byte_code):
+       * regex.c:
+       Redo diagnostic pragmas to pacify clang, too.
+       * dbusbind.c (xd_retrieve_arg): Do not use uninitialized variable.
+       * editfns.c (Fencode_time):
+       * fileio.c (file_accessible_directory_p):
+       * font.c (font_unparse_xlfd):
+       Use '&"string"[index]' instead of '"string" + (index)'.
+       * undo.c (user_error): Remove; unused.
+
 2013-05-16  Eli Zaretskii  <address@hidden>
 
        * insdel.c (insert_1_both): Document the arguments, instead of

=== modified file 'src/bytecode.c'
--- a/src/bytecode.c    2013-03-24 12:59:45 +0000
+++ b/src/bytecode.c    2013-05-18 05:32:17 +0000
@@ -660,9 +660,12 @@
         the table clearer.  */
 #define LABEL(OP) [OP] = &&insn_ ## OP
 
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)
 # pragma GCC diagnostic push
 # pragma GCC diagnostic ignored "-Woverride-init"
+#elif defined __clang__
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Winitializer-overrides"
 #endif
 
       /* This is the dispatch table for the threaded interpreter.  */
@@ -676,7 +679,7 @@
 #undef DEFINE
        };
 
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#if 4 < __GNUC__ + (6 <= __GNUC_MINOR__) || defined __clang__
 # pragma GCC diagnostic pop
 #endif
 

=== modified file 'src/dbusbind.c'
--- a/src/dbusbind.c    2013-01-02 16:13:04 +0000
+++ b/src/dbusbind.c    2013-05-18 05:32:17 +0000
@@ -882,7 +882,7 @@
 #endif
       {
        dbus_uint32_t val;
-       unsigned int pval = val;
+       unsigned int pval;
        dbus_message_iter_get_basic (iter, &val);
        pval = val;
        XD_DEBUG_MESSAGE ("%c %u", dtype, pval);

=== modified file 'src/editfns.c'
--- a/src/editfns.c     2013-04-02 01:54:56 +0000
+++ b/src/editfns.c     2013-05-18 05:32:17 +0000
@@ -1946,7 +1946,7 @@
          EMACS_INT zone_hr = abszone / (60*60);
          int zone_min = (abszone/60) % 60;
          int zone_sec = abszone % 60;
-         sprintf (tzbuf, tzbuf_format, "-" + (XINT (zone) < 0),
+         sprintf (tzbuf, tzbuf_format, &"-"[XINT (zone) < 0],
                   zone_hr, zone_min, zone_sec);
          tzstring = tzbuf;
        }

=== modified file 'src/fileio.c'
--- a/src/fileio.c      2013-05-07 21:34:03 +0000
+++ b/src/fileio.c      2013-05-18 05:32:17 +0000
@@ -2873,7 +2873,7 @@
         and it's a safe optimization here.  */
       char *buf = SAFE_ALLOCA (len + 3);
       memcpy (buf, file, len);
-      strcpy (buf + len, "/." + (file[len - 1] == '/'));
+      strcpy (buf + len, &"/."[file[len - 1] == '/']);
       dir = buf;
     }
 

=== modified file 'src/font.c'
--- a/src/font.c        2013-04-27 13:32:24 +0000
+++ b/src/font.c        2013-05-18 05:32:17 +0000
@@ -1219,7 +1219,7 @@
                return -1;
              f[j] = p = alloca (alloc);
              sprintf (p, "%s%s-*", SDATA (val),
-                      "*" + (SDATA (val)[SBYTES (val) - 1] == '*'));
+                      &"*"[SDATA (val)[SBYTES (val) - 1] == '*']);
            }
          else
            f[j] = SSDATA (val);
@@ -1618,7 +1618,7 @@
     }
   if (point_size > 0)
     {
-      int len = snprintf (p, lim - p, "-%d" + (p == name), point_size);
+      int len = snprintf (p, lim - p, &"-%d"[p == name], point_size);
       if (! (0 <= len && len < lim - p))
        return -1;
       p += len;

=== modified file 'src/regex.c'
--- a/src/regex.c       2013-05-15 00:52:07 +0000
+++ b/src/regex.c       2013-05-18 05:32:17 +0000
@@ -33,10 +33,9 @@
 
 /* Ignore some GCC warnings for now.  This section should go away
    once the Emacs and Gnulib regex code is merged.  */
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
+#if 4 < __GNUC__ + (5 <= __GNUC_MINOR__) || defined __clang__
 # pragma GCC diagnostic ignored "-Wstrict-overflow"
 # ifndef emacs
-#  pragma GCC diagnostic ignored "-Wunused-but-set-variable"
 #  pragma GCC diagnostic ignored "-Wunused-function"
 #  pragma GCC diagnostic ignored "-Wunused-macros"
 #  pragma GCC diagnostic ignored "-Wunused-result"
@@ -44,6 +43,10 @@
 # endif
 #endif
 
+#if 4 < __GNUC__ + (5 <= __GNUC_MINOR__) && ! defined __clang__
+# pragma GCC diagnostic ignored "-Wunused-but-set-variable"
+#endif
+
 #include <config.h>
 
 #include <stddef.h>

=== modified file 'src/undo.c'
--- a/src/undo.c        2013-01-08 19:13:31 +0000
+++ b/src/undo.c        2013-05-18 05:32:17 +0000
@@ -445,12 +445,6 @@
   unbind_to (count, Qnil);
 }
 
-static _Noreturn void
-user_error (const char *msg)
-{
-  xsignal1 (Quser_error, build_string (msg));
-}
-
 
 void
 syms_of_undo (void)