Change occurrences of gcc to the more general cc

This is done for the sake of Yosemite, which does not have gcc, and yet
this change is also compatible with Linux.

pkgs/applications/science/electronics/eagle/default.nix

@@ -59,11 +59,11 @@ stdenv.mkDerivation rec {
     gcc -shared -fPIC -DEAGLE_PATH=\"$out/eagle-${version}\" ${./eagle_fixer.c} -o "$out"/lib/eagle_fixer.so -ldl
 
     # Make wrapper script
-    dynlinker="$(cat $NIX_GCC/nix-support/dynamic-linker)"
+    dynlinker="$(cat $NIX_CC/nix-support/dynamic-linker)"
     mkdir -p "$out"/bin
     cat > "$out"/bin/eagle << EOF
     #!${stdenv.shell}
-    export LD_LIBRARY_PATH="${stdenv.gcc.gcc}/lib:${libPath}"
+    export LD_LIBRARY_PATH="${stdenv.cc.gcc}/lib:${libPath}"
     export LD_PRELOAD="$out/lib/eagle_fixer.so"
     exec "$dynlinker" "$out/eagle-${version}/bin/eagle" "\$@"
     EOF