> /usr/local/gcc43/bin/gcc -v
Using built-in specs.
Target: i386-apple-darwin9.2.0
Configured with: ../gcc/configure --prefix=/usr/local/gcc43 --enable-threads=posix --with-arch=core2 --with-tune=core2 --with-gmp=/sw --with-mpfr=/sw --disable-nls --disable-bootstrap --enable-checking=yes,rtl CFLAGS=-g LDFLAGS=/usr/lib/libiconv.dylib --enable-languages=c,c++,objc,obj-c++
Thread model: posix
gcc version 4.3.0 20080215 (experimental) (GCC) 

> /usr/local/gcc43/bin/gcc -O3 -fprofile-use -c pcx.i 
pcx.c: In function 'pcx_decode_frame':
pcx.c:247: error: Dead histogram
IOR value ior:0.
memset (dst_28, 0, 0);

pcx.c:247: internal compiler error: verify_histograms failed
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

I compiled ffmpeg profiled and didn't exercise code before doing -fprofile-use, so the stats are all empty.