gcc: drop libstdc++ patch (#445308)

pkgs/development/compilers/gcc/patches/default.nix

@@ -52,10 +52,7 @@ in
 
 ## 1. Patches relevant on every platform ####################################
 
-[ ]
+optionals noSysDirs (
-# Pass the path to a C++ compiler directly in the Makefile.in
-++ optional (!lib.systems.equals targetPlatform hostPlatform) ./libstdc++-target.patch
-++ optionals noSysDirs (
   [
     # Do not try looking for binaries and libraries in /lib and /usr/lib
     ./gcc-12-no-sys-dirs.patch

pkgs/development/compilers/gcc/patches/libstdc++-target.patch

@@ -1,32 +0,0 @@
-Patch to make the target libraries 'configure' scripts find the proper CPP.
-I noticed that building the mingw32 cross compiler.
-Looking at the build script for mingw in archlinux, I think that only nixos
-needs this patch. I don't know why.
-diff --git a/Makefile.in b/Makefile.in
-index 93f66b6..d691917 100644
---- a/Makefile.in
-+++ b/Makefile.in
-@@ -266,6 +266,7 @@ BASE_TARGET_EXPORTS = \
- 	AR="$(AR_FOR_TARGET)"; export AR; \
- 	AS="$(COMPILER_AS_FOR_TARGET)"; export AS; \
- 	CC="$(CC_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CC; \
-+	CPP="$(CC_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS -E"; export CC; \
- 	CFLAGS="$(CFLAGS_FOR_TARGET)"; export CFLAGS; \
- 	CONFIG_SHELL="$(SHELL)"; export CONFIG_SHELL; \
- 	CPPFLAGS="$(CPPFLAGS_FOR_TARGET)"; export CPPFLAGS; \
-@@ -291,11 +292,13 @@ BASE_TARGET_EXPORTS = \
- RAW_CXX_TARGET_EXPORTS = \
- 	$(BASE_TARGET_EXPORTS) \
- 	CXX_FOR_TARGET="$(RAW_CXX_FOR_TARGET)"; export CXX_FOR_TARGET; \
--	CXX="$(RAW_CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CXX;
-+	CXX="$(RAW_CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CXX; \
-+	CXXCPP="$(RAW_CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS -E"; export CXX;
- 
- NORMAL_TARGET_EXPORTS = \
- 	$(BASE_TARGET_EXPORTS) \
--	CXX="$(CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CXX;
-+	CXX="$(CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS"; export CXX; \
-+	CXXCPP="$(CXX_FOR_TARGET) $(XGCC_FLAGS_FOR_TARGET) $$TFLAGS -E"; export CXX;
- 
- # Where to find GMP
- HOST_GMPLIBS = @gmplibs@