uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/development/compilers/gcc/common/pre-configure.nix

@@ -0,0 +1,67 @@
+{ lib, version, hostPlatform, targetPlatform
+, gnatboot ? null
+, langAda ? false
+, langJava ? false
+, langJit ? false
+, langGo }:
+
+assert langJava -> lib.versionOlder version "7";
+assert langAda -> gnatboot != null;
+
+lib.optionalString (hostPlatform.isSunOS && hostPlatform.is64bit) ''
+  export NIX_LDFLAGS=`echo $NIX_LDFLAGS | sed -e s~$prefix/lib~$prefix/lib/amd64~g`
+  export LDFLAGS_FOR_TARGET="-Wl,-rpath,$prefix/lib/amd64 $LDFLAGS_FOR_TARGET"
+  export CXXFLAGS_FOR_TARGET="-Wl,-rpath,$prefix/lib/amd64 $CXXFLAGS_FOR_TARGET"
+  export CFLAGS_FOR_TARGET="-Wl,-rpath,$prefix/lib/amd64 $CFLAGS_FOR_TARGET"
+'' + lib.optionalString (lib.versionOlder version "7" && (langJava || langGo)) ''
+  export lib=$out;
+'' + lib.optionalString langAda ''
+  export PATH=${gnatboot}/bin:$PATH
+''
+
+# NOTE 2020/3/18: This environment variable prevents configure scripts from
+# detecting the presence of aligned_alloc on Darwin.  There are many facts that
+# collectively make this fix necessary:
+#  - Nix uses a fixed set of standard library headers on all MacOS systems,
+#    regardless of their actual version.  (Nix uses version 10.12 headers.)
+#  - Nix uses the native standard library binaries for the build system.  That
+#    means the standard library binaries may not exactly match the standard
+#    library headers.
+#  - The aligned_alloc procedure is present in MacOS 10.15 (Catalina), but not
+#    in earlier versions.  Therefore on Catalina systems, aligned_alloc is
+#    linkable (i.e. present in the binary libraries) but not present in the
+#    headers.
+#  - Configure scripts detect a procedure's existence by checking whether it is
+#    linkable.  They do not check whether it is present in the headers.
+#  - GCC throws an error during compilation because aligned_alloc is not
+#    defined in the headers---even though the linker can see it.
+#
+# This fix would not be necessary if ANY of the above were false:
+#  - If Nix used native headers for each different MacOS version, aligned_alloc
+#    would be in the headers on Catalina.
+#  - If Nix used the same libary binaries for each MacOS version, aligned_alloc
+#    would not be in the library binaries.
+#  - If Catalina did not include aligned_alloc, this wouldn't be a problem.
+#  - If the configure scripts looked for header presence as well as
+#    linkability, they would see that aligned_alloc is missing.
+#  - If GCC allowed implicit declaration of symbols, it would not fail during
+#    compilation even if the configure scripts did not check header presence.
+#
++ lib.optionalString (hostPlatform.isDarwin) ''
+  export ac_cv_func_aligned_alloc=no
+''
+
+# In order to properly install libgccjit on macOS Catalina, strip(1)
+# upon installation must not remove external symbols, otherwise the
+# install step errors with "symbols referenced by indirect symbol
+# table entries that can't be stripped".
++ lib.optionalString (hostPlatform.isDarwin && langJit) ''
+  export STRIP='strip -x'
+''
+
+# HACK: if host and target config are the same, but the platforms are
+# actually different we need to convince the configure script that it
+# is in fact building a cross compiler although it doesn't believe it.
++ lib.optionalString (targetPlatform.config == hostPlatform.config && targetPlatform != hostPlatform) ''
+  substituteInPlace configure --replace is_cross_compiler=no is_cross_compiler=yes
+''