[igraph] compiling under Mac OS X

[Vincent Matossian]

 I'm getting make running into the following error 

...
Making all in src
/bin/sh ../ylwrap `test -f 'foreign-ncol-parser.y' || echo './'`foreign-ncol-parser.y y.tab.c foreign-ncol-parser.c
 y.tab.h foreign-ncol-parser.h y.output foreign-ncol-parser.output -- bison -y  -d
/Users/vincent/igraph--main--0.5--patch-4/src/foreign-ncol-parser.y:64: unrecognized: %output
....

followed by a few lines of similar issues for the % directives in .y files.

Any idea what could be causing this?

gcc 4.0.1. autoconf 2.59. config.log is attached.

Thanks!

config.log
Description: Binary data