guile-zlib: fix path to zlib (#497498)

pkgs/by-name/gu/guile-zlib/guile-zlib-change-zlib-path-from-libdir-to-sharedlibdir.diff

@@ -0,0 +1,12 @@
+diff --git a/configure.ac b/configure.ac
+--- a/configure.ac
++++ b/configure.ac
+@@ -30,7 +30,7 @@ fi
+ 
+ PKG_CHECK_MODULES([LIBZ], [zlib])
+ AC_MSG_CHECKING([libz library directory])
+-PKG_CHECK_VAR([LIBZ_LIBDIR], [zlib], [libdir])
++PKG_CHECK_VAR([LIBZ_LIBDIR], [zlib], [sharedlibdir])
+ AC_MSG_RESULT([$LIBZ_LIBDIR])
+ AS_IF([test "x$LIBZ_LIBDIR" = "x"], [
+   AC_MSG_FAILURE([Unable to identify libz lib path.])

pkgs/by-name/gu/guile-zlib/package.nix

@@ -21,6 +21,11 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-aaZhwHimQq408DNtHy442kh/EYdRdxP0Z1tQGDKmkmc=";
   };
 
+  patches = [
+    # fix path to libz.so to sharedlibdir from zlib.pc
+    ./guile-zlib-change-zlib-path-from-libdir-to-sharedlibdir.diff
+  ];
+
   strictDeps = true;
   nativeBuildInputs = [
     autoreconfHook