toolchain: add patch to fix cpp in gcc-10

tools/toolchain/scripts/files/gcc-10.2.0-cpp-__has_include.patch

@@ -0,0 +1,40 @@
+From b7bb13d4a5fcb593dc745ca3b6180f8babb54893 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Tiziano=20M=C3=BCller?= <tiziano.mueller@chem.uzh.ch>
+Date: Mon, 27 Jul 2020 15:40:38 +0200
+Subject: [PATCH] libcpp: fix __has_include handling with traditional-cpp
+
+fixes #95889
+---
+ libcpp/init.c        | 3 +++
+ libcpp/traditional.c | 4 +++-
+ 2 files changed, 6 insertions(+), 1 deletion(-)
+
+diff --git a/libcpp/init.c b/libcpp/init.c
+index 0aac5acd0a35..b0cf71192589 100644
+--- a/libcpp/init.c
++++ b/libcpp/init.c
+@@ -400,6 +400,9 @@ static const struct builtin_macro builtin_array[] =
+   B("__LINE__",		 BT_SPECLINE,      true),
+   B("__INCLUDE_LEVEL__", BT_INCLUDE_LEVEL, true),
+   B("__COUNTER__",	 BT_COUNTER,       true),
++  /* Make sure to update the list of built-in
++     function-like macros in traditional.c:
++     fun_like_macro() when adding more following */
+   B("__has_attribute",	 BT_HAS_ATTRIBUTE, true),
+   B("__has_cpp_attribute", BT_HAS_ATTRIBUTE, true),
+   B("__has_builtin",	 BT_HAS_BUILTIN,   true),
+diff --git a/libcpp/traditional.c b/libcpp/traditional.c
+index 77adb3bf595f..b087072c9b4c 100644
+--- a/libcpp/traditional.c
++++ b/libcpp/traditional.c
+@@ -330,7 +330,9 @@ fun_like_macro (cpp_hashnode *node)
+ {
+   if (cpp_builtin_macro_p (node))
+     return (node->value.builtin == BT_HAS_ATTRIBUTE
+-	    || node->value.builtin == BT_HAS_BUILTIN);
++	    || node->value.builtin == BT_HAS_BUILTIN
++	    || node->value.builtin == BT_HAS_INCLUDE
++	    || node->value.builtin == BT_HAS_INCLUDE_NEXT);
+   return node->value.macro->fun_like;
+ }
+

tools/toolchain/scripts/install_gcc.sh

@@ -4,6 +4,11 @@ SCRIPT_DIR="$(cd "$(dirname "$SCRIPT_NAME")" && pwd -P)"
 
 gcc_ver="10.2.0"
 gcc_sha256="27e879dccc639cd7b0cc08ed575c1669492579529b53c9ff27b0b96265fa867d"
+
+patches=(
+    "${SCRIPT_DIR}/files/gcc-${gcc_ver}-cpp-__has_include.patch"
+    )
+
 source "${SCRIPT_DIR}"/common_vars.sh
 source "${SCRIPT_DIR}"/tool_kit.sh
 source "${SCRIPT_DIR}"/signal_trap.sh
@@ -41,6 +46,11 @@ case "$with_gcc" in
             fi
             echo "Installing GCC from scratch into ${pkg_install_dir}"
             cd gcc-${gcc_ver}
+
+            for patch in "${patches[@]}" ; do
+                patch -p1 < "${patch}"
+            done
+
             ./contrib/download_prerequisites > prereq.log 2>&1
             GCCROOT=${PWD}
             mkdir obj