Mingw changes to gcc.
Mingw changes to gcc.

Removing a gcc flag, --enable-version-specific-runtime-libs, that put gcc libs
in a speparate directory instead of /lib; this broke the installation of
libgcc_s.a for the case of "--enable-shared" in mingw-w64. And we already have all gccs in directories apart.

I also add the option --enable-fully-dynamic-string, which is used in the
prebuilt mingw64 toolchain; this way nixpkgs creates ABI-compatible binaries
with mingw64 upstream. (told by jon_y on irc ##mingw)


svn path=/nixpkgs/trunk/; revision=34242

SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,triton/triton,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,triton/triton,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,triton/triton,triton/triton,SymbiFlow/nixpkgs,NixOS/nixpkgs,triton/triton,triton/triton,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,triton/triton,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,triton/triton,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs