[libgfortran,patch] Add fallback functions tgamma, lgamma, tgammaf and lgammaf

[FX Coudert]

> Should one build GFC with a special recipe?

You need to build GCC, then edit ${builddir}/${target}/{,*/} 
libgfortran/config.h to remove the lines that define HAVE_{T,L}GAMMA 
{F,}, and rebuild the libgfortrans. There might be some deep autoconf  
magic to do that, but I don't know it.

Alternatively, you could (before building) remove the lines checking  
for {t,l}gamma{f,} in libgfortran/configure.ac, regenerate  
config.h.in and configure, and then build.

But of course, the best thing to do is: report this bug to cygwin/glibc.

FX