glib fails to build with gcc 4.8.2 on Lion

[mistydemeo]

Logs: https://gist.github.com/mistydemeo/2fc344d92d1d3dae7724

A couple of errors in gdummyfile.c:

libtool: compile: gcc-4.8 -DHAVE_CONFIG_H -I. -I.. -I/usr/local/Cellar/zlib/1.2.8/include -DG_LOG_DOMAIN=\"GLib-GIO\" -I.. -I../glib -I../glib -I.. -I../gmodule -DG_DISABLE_CAST_CHECKS -DGIO_COMPILATION -DGIO_MODULE_DIR=\"/usr/local/lib/gio/modules\" -I/usr/local/opt/zlib/include -I/usr/local/opt/gettext/include -F/usr/local/Frameworks -D_REENTRANT -Wall -Wstrict-prototypes -Werror=declaration-after-statement -Werror=missing-prototypes -Werror=implicit-function-declaration -Werror=pointer-arith -Werror=init-self -Werror=format=2 -Werror=missing-include-dirs -fvisibility=hidden -xobjective-c -Os -w -pipe -mcpu=7450 -faltivec -mmacosx-version-min=10.4 -c gdummyfile.c -fno-common -DPIC -o .libs/libgio_2_0_la-gdummyfile.o
gdummyfile.c: In function 'unescape_string':
gdummyfile.c:462:8: error: expected expression before 'in'
for (in = escaped_string; in < escaped_string_end; in++)
^
gdummyfile.c: In function '_g_decode_uri':
gdummyfile.c:559:8: error: expected expression before 'in'
for (in = uri; in < p - 1; in++)
^

This doesn't happen with any Apple compilers.

(Note that the logs are from Tiger, but the same thing happens on x86_64 Lion with GCC 4.8.2.)

Upstream bug report: https://bugzilla.gnome.org/show_bug.cgi?id=672777

[mistydemeo]

The functions themselves seem harmless enough, unless I'm missing something:

static char *
unescape_string (const gchar *escaped_string,
         const gchar *escaped_string_end,
         const gchar *illegal_characters)
{
  const gchar *in;
  gchar *out, *result;
  gint character;

  if (escaped_string == NULL)
    return NULL;

  if (escaped_string_end == NULL)
    escaped_string_end = escaped_string + strlen (escaped_string);

  result = g_malloc (escaped_string_end - escaped_string + 1);

  out = result;
  for (in = escaped_string; in < escaped_string_end; in++) 

...

[manphiz]

The problem seems to be that on Mac sources for libgio is being compiled as objective-c sources (see gio/Makefile.am:504), but GNU GCC doesn't handle this well. When I dropped the "-xobjective-c" switch it works. I'll update upstream bug report with more details.

[mistydemeo]

Upstream had a similar suggestion:

 This is probably somehow a side effect of us building gio with "-xobjective-c".

from gio/Makefile.am:

  # This is dumb.  The ObjC source file should be properly named .m
  libgio_2_0_la_CFLAGS += -xobjective-c

So, what happens if you rename gnextstepsettingsbackend.c to
gnextstepsettingsbackend.m, and then remove the line above?

[mistydemeo]

Hilariously, when I apply the recommended patch, GCC appears to choke on a core OS header instead:

In file included from /System/Library/Frameworks/Foundation.framework/Headers/Foundation.h:120:0,
                 from gnextstepsettingsbackend.m:28:
/System/Library/Frameworks/Foundation.framework/Headers/NSTask.h:75:24: error: expected identifier or '(' before '^' token
 @property (copy) void (^terminationHandler)(NSTask *) NS_AVAILABLE(10_7, NA);
                        ^
/System/Library/Frameworks/Foundation.framework/Headers/NSTask.h:78:1: error: expected identifier before 'end'
 @end
 ^

Which I can't really blame on GNOME.

[mistydemeo]

I see this happening in vim too:

In file included from /System/Library/Frameworks/AppKit.framework/Headers/AppKit.h:194:0,
                 from /System/Library/Frameworks/Cocoa.framework/Headers/Cocoa.h:13,
                 from os_macosx.m:24:
/System/Library/Frameworks/AppKit.framework/Headers/NSWindowRestoration.h:119:116: error: expected ')' before '^' token
 - (void)restoreDocumentWindowWithIdentifier:(NSString *)identifier state:(NSCoder *)state completionHandler:(void (^)(NSWindow *, NSError *))completionHandler NS_AVAILABLE_MAC(10_7);

      ^
/System/Library/Frameworks/AppKit.framework/Headers/NSWindowRestoration.h:119:118: error: expected ')' before '(' token
 - (void)restoreDocumentWindowWithIdentifier:(NSString *)identifier state:(NSCoder *)state completionHandler:(void (^)(NSWindow *, NSError *))completionHandler NS_AVAILABLE_MAC(10_7);

        ^
gcc-4.8 -c -I. -Iproto -DHAVE_CONFIG_H   -F/usr/local/Frameworks -DMACOS_X_UNIX  -Os -w -pipe -march=core2 -msse4.1 -mmacosx-version-min=10.7 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1       -o objects/main.o main.c
make[1]: *** [objects/os_macosx.o] Error 1

Maybe it doesn't like the NS_AVAILABLE_MAC macros?

(vim compiled fine on 10.4, including the ObjC parts.)

[mistydemeo]

glib also works fine on 10.4.

[mistydemeo]

Since this fixed something, and doesn't break anything, I went ahead and integrated the fix upstream suggested.