* libc/include/math.h (signgam): Change to errno-like solution
using a function to return the address of the real signgam.
* libc/reent/signgam.c: New file containing __signgam().
* libc/reent/Makefile.am: Added signgam.c to list of files.
* libc/reent/Makefile.in: Regenerated.
Jeff Johnston