Cygwin crashing when building gmp library
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I'm trying to build the gmp library using cygwin. At a point in the configure process, it crashes, telling me that 

> no usable M4 in $PATH or /usr/5bin

I think that this means it is looking for MinGW, under which MSYS and M4 exist. I have verified that my path variable contains 

> c:\mingw\msys

which is where I believe M4 exists, no? Can anyone help me figure out why this is crashing?

Thanks!