Created attachment 253319 [details]
Sample C code.

Overview: 
When compiling attached C code with g++ compilation fails, because ld complains about undefined references to g_settings_schema_* functions.

Steps to Reproduce:
Just try to compile attached code both with gcc and g++, below I provide g++ compilation log:

g++ test.c -o test `pkg-config gio-2.0 --cflags --libs`
test.c: In function ‘int main()’:
test.c:6:5: warning: ‘void g_type_init()’ is deprecated (declared at /usr/include/glib-2.0/gobject/gtype.h:669) [-Wdeprecated-declarations]
     g_type_init();
     ^
test.c:6:17: warning: ‘void g_type_init()’ is deprecated (declared at /usr/include/glib-2.0/gobject/gtype.h:669) [-Wdeprecated-declarations]
     g_type_init();
                 ^
/tmp/ccNVIz8R.o: In function `main':
test.c:(.text+0xe): undefined reference to `g_settings_schema_source_get_default()'
test.c:(.text+0x3e): undefined reference to `g_settings_schema_source_ref(_GSettingsSchemaSource*)'
test.c:(.text+0x58): undefined reference to `g_settings_schema_source_lookup(_GSettingsSchemaSource*, char const*, int)'
test.c:(.text+0xb4): undefined reference to `g_settings_schema_source_unref(_GSettingsSchemaSource*)'
collect2: error: ld returned 1 exit status

Analogical compilation, but with gcc, results with properly working executable. 

Additional information:
I am running Arch Linux x64 with glib v2.36.4, gcc/g++ v4.8.1, ld v2.23.2