GCC compilation yields “real.h:53: error: 'SIZEOF_LONG' undeclared here (not in a function)”

Question

I\'m trying to compile GCC 4.7.2 on a Buffalo LinkStation Pro Duo (after unlocking it) which runs Linux 2.6.31.8 armv5tel.

Unfortunately, make throws qu

Answer 1

• Thanks to chill's answer I checked config.log to discover
  conftest.c:10:19: error: ppl_c.h: No such file or directory
  (which, curiously, did not prevent configure from creating a Makefile and returning a success error code). The first google hit on that was this post, showing I didn't provide the ppl dependency.
• The ppl-1.0 compilation greeted me with
  checked_float.inlines.hh:1012: error: 'frexpl' was not declared in this scope
  which led me to this post suggesting I'd use the 1.1 snapshot instead, which worked
• Now, gcc's make offered me another "helpful" error:
  gcc/../libcpp/include/line-map.h:66: error: 'CHAR_BIT'
  which turned out to be due to C_INCLUDE_PATH ending with a colon (I already experienced the checking LIBRARY_PATH variable... contains current directory error mentioned in that post, but didn't think about checking other variables for that as well)

Compilation is still running, so far no more errors...