/usr/src/gcc-6/debian/patches/gcc-auto-build.diff is in gcc-6-source 6.4.0-17ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | # DP: Fix cross building a native compiler.
Index: b/src/gcc/configure.ac
===================================================================
--- a/src/gcc/configure.ac
+++ b/src/gcc/configure.ac
@@ -1686,7 +1686,7 @@ else
# Clearing GMPINC is necessary to prevent host headers being
# used by the build compiler. Defining GENERATOR_FILE stops
# system.h from including gmp.h.
- CC="${CC_FOR_BUILD}" CFLAGS="${CFLAGS_FOR_BUILD}" \
+ CC="${CC_FOR_BUILD}" CFLAGS="${CFLAGS_FOR_BUILD} -DGENERATOR_FILE" \
CXX="${CXX_FOR_BUILD}" CXXFLAGS="${CXXFLAGS_FOR_BUILD}" \
LD="${LD_FOR_BUILD}" LDFLAGS="${LDFLAGS_FOR_BUILD}" \
GMPINC="" CPPFLAGS="${CPPFLAGS} -DGENERATOR_FILE" \
|