ijtrotts@localhost:/tmp$ gcc objc_float_bug.m  -lobjc
ijtrotts@localhost:/tmp$ ./a.out
objc_write_type: cannot parse typespec: f
Aborted
ijtrotts@localhost:/tmp$ cat objc_float_bug.m
#include <objc/Object.h>

int main()
{
    float x=1.25;
    TypedStream* stream =
        objc_open_typed_stream_for_file("foo",OBJC_WRITEONLY);
    objc_write_type(stream, @encode(float), &x);
    objc_close_typed_stream(stream);
    return 0;
}

ijtrotts@localhost:/tmp$ gcc -v
Reading specs from /usr/local/lib/gcc-lib/i686-pc-linux-gnu/3.3.5/specs
Configured with: ../gcc-3.3.5/configure --enable-languages=c,c++,f77,objc --enable-objc-gc
Thread model: posix
gcc version 3.3.5