gcc: Use upstream fix for cross-canadian builds

Replace the patch from #1600 with the change that landed upstream.

Signed-off-by: Chris Packham <judge.packham@gmail.com>

2 files changed, 78 insertions, 47 deletions

diff --git a/packages/gcc/11.2.0/0005-Fix-cross-native-cross-caandian-builds.patch b/packages/gcc/11.2.0/0005-Fix-cross-native-cross-caandian-builds.patch
deleted file mode 100644
index 633f8ea..0000000
--- a/packages/gcc/11.2.0/0005-Fix-cross-native-cross-caandian-builds.patch
+++ /dev/null
@@ -1,47 +0,0 @@
-From 7f13ba28a4aac454ada29552acdf9a44697ad5a8 Mon Sep 17 00:00:00 2001
-From: Alexey Brodkin <abrodkin@synopsys.com>
-Date: Wed, 15 Sep 2021 01:08:06 -0700
-Subject: [PATCH] Fix cross-native/cross-caandian builds
-
-See upstream bug report [1] for more details.
-Basically when we do cross-canadian build with
-use of the same GCC11 as a "host" compiler we're seeing
-an error like that:
-------------------->8-------------------
-mingw-w64-cross/gcc/x86_64-w64-mingw32/libstdc++-v3/include/fenv.h:58:11: error: 'fenv_t' has not been declared in '::'
-   58 |   using ::fenv_t;
-------------------->8-------------------
-
-This is a solution proposed by Yujie Yang in [2]
-
-[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100017
-[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100017#c20
-
-Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
----
- configure    |    2 +-
- configure.ac |    2 +-
- 2 files changed, 2 insertions(+), 2 deletions(-)
-
---- a/configure
-+++ b/configure
-@@ -16478,7 +16478,7 @@
- fi
- 
- 
--RAW_CXX_FOR_TARGET="$CXX_FOR_TARGET"
-+RAW_CXX_FOR_TARGET="$CXX_FOR_TARGET -nostdinc++"
- 
- { $as_echo "$as_me:${as_lineno-$LINENO}: checking where to find the target ar" >&5
- $as_echo_n "checking where to find the target ar... " >&6; }
---- a/configure.ac
-+++ b/configure.ac
-@@ -3520,7 +3520,7 @@
- ACX_CHECK_INSTALLED_TARGET_TOOL(WINDRES_FOR_TARGET, windres)
- ACX_CHECK_INSTALLED_TARGET_TOOL(WINDMC_FOR_TARGET, windmc)
- 
--RAW_CXX_FOR_TARGET="$CXX_FOR_TARGET"
-+RAW_CXX_FOR_TARGET="$CXX_FOR_TARGET -nostdinc++"
- 
- GCC_TARGET_TOOL(ar, AR_FOR_TARGET, AR, [binutils/ar])
- GCC_TARGET_TOOL(as, AS_FOR_TARGET, AS, [gas/as-new])
diff --git a/packages/gcc/11.2.0/0005-libstdc-Add-nostdinc-for-c-17-sources-PR100017.patch b/packages/gcc/11.2.0/0005-libstdc-Add-nostdinc-for-c-17-sources-PR100017.patch
new file mode 100644
index 0000000..8851e98
--- /dev/null
+++ b/packages/gcc/11.2.0/0005-libstdc-Add-nostdinc-for-c-17-sources-PR100017.patch
@@ -0,0 +1,78 @@
+From 4fde88e5dd152fe866a97b12e0f8229970d15cb3 Mon Sep 17 00:00:00 2001
+From: Jonathan Wakely <jwakely@redhat.com>
+Date: Fri, 7 Jan 2022 15:21:03 +0000
+Subject: [PATCH] libstdc++: Add -nostdinc++ for c++17 sources [PR100017]
+
+When building a build!=host compiler, the just-built gcc can't be used
+to build the target libstdc++ (because it is built for the host triplet,
+not the build triplet). The top-level configure.ac sets up the build
+flags for libstdc++ (and other "raw_cxx" libs) like this:
+
+GCC_TARGET_TOOL(c++ for libstdc++, RAW_CXX_FOR_TARGET, CXX,
+		[gcc/xgcc -shared-libgcc -B$$r/$(HOST_SUBDIR)/gcc -nostdinc++ -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/src -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/src/.libs -L$$r/$(TARGET_SUBDIR)/libstdc++-v3/libsupc++/.libs],
+		c++)
+
+The -nostdinc++ flag is only used for the IN-TREE-TOOL, i.e. when using
+the just-built gcc/xgcc compiler. This means that the cross-compiler
+used to build libstdc++ will add its own libstdc++ headers to the
+include path. That results in the #include <cfenv> in
+src/c++17/floating_to_chars.cc and src/c++17/floating_from_chars.cc
+doing #include_next <fenv.h> and finding the libstdc++ fenv.h wrapper
+from the host compiler. Because that has the same include guard as the
+<fenv.h> in the libstdc++ we're trying to build, we never reach the
+underlying <fenv.h> from libc. That results in several errors of the
+form:
+
+error: 'fenv_t' has not been declared in '::'
+
+The most correct fix would be to add -nostdinc++ to the
+RAW_CXX_FOR_TARGET variable in configure.ac, or the
+RAW_CXX_TARGET_EXPORTS variable in Makefile.tpl.
+
+Another solution would be to make the libstdc++ <fenv.h> wrapper use
+_GLIBCXX_INCLUDE_NEXT_C_HEADERS like our <stdlib.h> and other C header
+wrappers.
+
+For now though, the simplest and safest solution is to just add
+-nostdinc++ to the CXXFLAGS used for src/c++17/*.cc, which is what this
+does.
+
+libstdc++-v3/ChangeLog:
+
+	PR libstdc++/100017
+	* src/c++17/Makefile.am (AM_CXXFLAGS): Add -nostdinc++.
+	* src/c++17/Makefile.in: Regenerate.
+---
+ libstdc++-v3/src/c++17/Makefile.am | 2 +-
+ libstdc++-v3/src/c++17/Makefile.in | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/libstdc++-v3/src/c++17/Makefile.am b/libstdc++-v3/src/c++17/Makefile.am
+index f08553a1dd78..3d53f652fac9 100644
+--- a/libstdc++-v3/src/c++17/Makefile.am
++++ b/libstdc++-v3/src/c++17/Makefile.am
+@@ -79,7 +79,7 @@ endif
+ # OPTIMIZE_CXXFLAGS on the compile line so that -O2 can be overridden
+ # as the occasion calls for it.
+ AM_CXXFLAGS = \
+-	-std=gnu++17 \
++	-std=gnu++17 -nostdinc++ \
+ 	$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+ 	$(XTEMPLATE_FLAGS) $(VTV_CXXFLAGS) \
+ 	$(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS) \
+diff --git a/libstdc++-v3/src/c++17/Makefile.in b/libstdc++-v3/src/c++17/Makefile.in
+index 63984ecd52ad..8c02be6514f8 100644
+--- a/libstdc++-v3/src/c++17/Makefile.in
++++ b/libstdc++-v3/src/c++17/Makefile.in
+@@ -455,7 +455,7 @@ libc__17convenience_la_SOURCES = $(sources)  $(inst_sources)
+ # OPTIMIZE_CXXFLAGS on the compile line so that -O2 can be overridden
+ # as the occasion calls for it.
+ AM_CXXFLAGS = \
+-	-std=gnu++17 \
++	-std=gnu++17 -nostdinc++ \
+ 	$(glibcxx_lt_pic_flag) $(glibcxx_compiler_shared_flag) \
+ 	$(XTEMPLATE_FLAGS) $(VTV_CXXFLAGS) \
+ 	$(WARN_CXXFLAGS) $(OPTIMIZE_CXXFLAGS) $(CONFIG_CXXFLAGS) \
+-- 
+2.34.1
+