Broken bootstrap on Cygwin

[Angelo Graziosi]

Current trunk, rev. 169888, fails to bootstrap on Cygwin with this error:

[...]
/tmp/gcc-4.6-r169888/libgcc/config/libbid/bid_decimal_globals.c:47:18: 
fatal error: fenv.h: No such file or directory
compilation terminated.
make[2]: *** [bid_decimal_globals.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: Leaving directory `/tmp/gcc-4.6-r169888/Work/i686-pc-cygwin/libgcc'
make[1]: *** [all-target-libgcc] Error 2
make[1]: Leaving directory `/tmp/gcc-4.6-r169888/Work'
make: *** [all] Error 2


usually I do weekly builds without any problem configuring with

$ gcc-4.6 -v
Using built-in specs.
COLLECT_GCC=gcc-4.6
COLLECT_LTO_WRAPPER=/usr/local/gfortran/libexec/gcc/i686-pc-cygwin/4.6.0/lto-wrapper.exe
Target: i686-pc-cygwin
Configured with: /tmp/gcc-4.6-r169403/configure 
--prefix=/usr/local/gfortran --program-suffix=-4.6 
--enable-languages=c,c++,fortran --enable-checking=release 
--enable-threads=posix --enable-libgomp --disable-bootstrap 
--disable-libmudflap --disable-shared
Thread model: posix
gcc version 4.6.0 20110130 (experimental) (GCC)


Ciao,
Angelo.