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-rwxr-xr-xscripts/dummy-tools/gcc106
1 files changed, 106 insertions, 0 deletions
diff --git a/scripts/dummy-tools/gcc b/scripts/dummy-tools/gcc
new file mode 100755
index 0000000000..07f6dc4c5c
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+++ b/scripts/dummy-tools/gcc
@@ -0,0 +1,106 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Staring v4.18, Kconfig evaluates compiler capabilities, and hides CONFIG
+# options your compiler does not support. This works well if you configure and
+# build the kernel on the same host machine.
+#
+# It is inconvenient if you prepare the .config that is carried to a different
+# build environment (typically this happens when you package the kernel for
+# distros) because using a different compiler potentially produces different
+# CONFIG options than the real build environment. So, you probably want to make
+# as many options visible as possible. In other words, you need to create a
+# super-set of CONFIG options that cover any build environment. If some of the
+# CONFIG options turned out to be unsupported on the build machine, they are
+# automatically disabled by the nature of Kconfig.
+#
+# However, it is not feasible to get a full-featured compiler for every arch.
+# Hence these dummy toolchains to make all compiler tests pass.
+#
+# Usage:
+#
+# From the top directory of the source tree, run
+#
+# $ make CROSS_COMPILE=scripts/dummy-tools/ oldconfig
+#
+# Most of compiler features are tested by cc-option, which simply checks the
+# exit code of $(CC). This script does nothing and just exits with 0 in most
+# cases. So, $(cc-option, ...) is evaluated as 'y'.
+#
+# This scripts caters to more checks; handle --version and pre-process __GNUC__
+# etc. to pretend to be GCC, and also do right things to satisfy some scripts.
+
+# Check if the first parameter appears in the rest. Succeeds if found.
+# This helper is useful if a particular option was passed to this script.
+# Typically used like this:
+# arg_contain <word-you-are-searching-for> "$@"
+arg_contain ()
+{
+ search="$1"
+ shift
+
+ while [ $# -gt 0 ]
+ do
+ if [ "$search" = "$1" ]; then
+ return 0
+ fi
+ shift
+ done
+
+ return 1
+}
+
+# To set CONFIG_CC_IS_GCC=y
+if arg_contain --version "$@"; then
+ echo "gcc (scripts/dummy-tools/gcc)"
+ exit 0
+fi
+
+if arg_contain -E "$@"; then
+ # For scripts/cc-version.sh; This emulates GCC 20.0.0
+ if arg_contain - "$@"; then
+ sed -n '/^GCC/{s/__GNUC__/20/; s/__GNUC_MINOR__/0/; s/__GNUC_PATCHLEVEL__/0/; p;}; s/__LONG_DOUBLE_128__/1/ p'
+ exit 0
+ else
+ echo "no input files" >&2
+ exit 1
+ fi
+fi
+
+# To set CONFIG_AS_IS_GNU
+if arg_contain -Wa,--version "$@"; then
+ echo "GNU assembler (scripts/dummy-tools) 2.50"
+ exit 0
+fi
+
+if arg_contain -S "$@"; then
+ # For scripts/gcc-x86-*-has-stack-protector.sh
+ if arg_contain -fstack-protector "$@"; then
+ if arg_contain -mstack-protector-guard-reg=fs "$@"; then
+ echo "%fs"
+ else
+ echo "%gs"
+ fi
+ exit 0
+ fi
+
+ # For arch/powerpc/tools/gcc-check-mprofile-kernel.sh
+ if arg_contain -m64 "$@" && arg_contain -mprofile-kernel "$@"; then
+ if ! test -t 0 && ! grep -q notrace; then
+ echo "_mcount"
+ fi
+ exit 0
+ fi
+fi
+
+# To set GCC_PLUGINS
+if arg_contain -print-file-name=plugin "$@"; then
+ # Use $0 to find the in-tree dummy directory
+ echo "$(dirname "$(readlink -f "$0")")/dummy-plugin-dir"
+ exit 0
+fi
+
+# inverted return value
+if arg_contain -D__SIZEOF_INT128__=0 "$@"; then
+ exit 1
+fi