gcc error

../../gcc-4.4.4/gcc/gimple.h: In function ‘gimple_return_retval’:
../../gcc-4.4.4/gcc/system.h:577:55: warning: ISO C does not support ‘__FUNCTION__’ predefined identifier [-Wpedantic]
    ((void)(!(EXPR) ? fancy_abort (__FILE__, __LINE__, __FUNCTION__), 0 : 0))
                                                       ^
../../gcc-4.4.4/gcc/gimple.h:4102:3: note: in expansion of macro ‘gcc_assert’
   gcc_assert (gimple_num_ops (gs) == 1);
   ^
../../gcc-4.4.4/gcc/gimple.h: In function ‘gimple_return_set_retval’:
../../gcc-4.4.4/gcc/system.h:577:55: warning: ISO C does not support ‘__FUNCTION__’ predefined identifier [-Wpedantic]
    ((void)(!(EXPR) ? fancy_abort (__FILE__, __LINE__, __FUNCTION__), 0 : 0))
                                                       ^
../../gcc-4.4.4/gcc/gimple.h:4113:3: note: in expansion of macro ‘gcc_assert’
   gcc_assert (gimple_num_ops (gs) == 1);
   ^
../../gcc-4.4.4/gcc/system.h:577:55: warning: ISO C does not support ‘__FUNCTION__’ predefined identifier [-Wpedantic]
    ((void)(!(EXPR) ? fancy_abort (__FILE__, __LINE__, __FUNCTION__), 0 : 0))
                                                       ^
../../gcc-4.4.4/gcc/gimple.h:4114:3: note: in expansion of macro ‘gcc_assert’
   gcc_assert (retval == NULL_TREE
   ^
../../gcc-4.4.4/gcc/gimple.h: In function ‘gimple_cdt_set_new_type’:
../../gcc-4.4.4/gcc/system.h:577:55: warning: ISO C does not support ‘__FUNCTION__’ predefined identifier [-Wpedantic]
    ((void)(!(EXPR) ? fancy_abort (__FILE__, __LINE__, __FUNCTION__), 0 : 0))
                                                       ^
../../gcc-4.4.4/gcc/gimple.h:4178:3: note: in expansion of macro ‘gcc_assert’
   gcc_assert (TREE_CODE_CLASS (TREE_CODE (new_type)) == tcc_type);
   ^
../../gcc-4.4.4/gcc/toplev.c: At top level:
../../gcc-4.4.4/gcc/toplev.c:536:1: error: redefinition of ‘floor_log2’
 floor_log2 (unsigned HOST_WIDE_INT x)
 ^
In file included from ../../gcc-4.4.4/gcc/toplev.c:58:0:
../../gcc-4.4.4/gcc/toplev.h:190:1: note: previous definition of ‘floor_log2’ was here
 floor_log2 (unsigned HOST_WIDE_INT x)
 ^
../../gcc-4.4.4/gcc/toplev.c:571:1: error: redefinition of ‘exact_log2’
 exact_log2 (unsigned HOST_WIDE_INT x)
 ^
In file included from ../../gcc-4.4.4/gcc/toplev.c:58:0:
../../gcc-4.4.4/gcc/toplev.h:196:1: note: previous definition of ‘exact_log2’ was here
 exact_log2 (unsigned HOST_WIDE_INT x)
 ^
Makefile:2470: recipe for target 'toplev.o' failed
make[2]: *** [toplev.o] Error 1
make[2]: Leaving directory '/tmp/rbdev-build/build-gcc/gcc'
Makefile:4863: recipe for target 'all-gcc' failed
make[1]: *** [all-gcc] Error 2
make[1]: Leaving directory '/tmp/rbdev-build/build-gcc'
Makefile:738: recipe for target 'all' failed
make: *** [all] Error 2