diff --git a/debian/changelog b/debian/changelog
index 0d8764c0..c3123278 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,10 @@
+llvm-toolchain-8 (1:8~+rc2-1~exp2) unstable; urgency=medium
+
+  * Activate -DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN for all
+    gcc
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Fri, 08 Feb 2019 21:34:32 +0100
+
 llvm-toolchain-8 (1:8~+rc2-1~exp1) unstable; urgency=medium
 
   * New snapshot release
diff --git a/debian/rules b/debian/rules
index b89ad3ed..8312655b 100755
--- a/debian/rules
+++ b/debian/rules
@@ -369,6 +369,7 @@ override_dh_auto_configure: preconfigure
 	-DPOLLY_BUNDLED_JSONCPP=OFF \
 	-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="WebAssembly;AVR" \
 	-DCLANG_ENABLE_BOOTSTRAP=ON \
+	-DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON \
 	-DCLANG_VENDOR=$(VENDOR) \
 	-DCLANG_BOOTSTRAP_PASSTHROUGH="CMAKE_INSTALL_PREFIX;CMAKE_VERBOSE_MAKEFILE;CMAKE_BUILD_TYPE;CMAKE_CXX_FLAGS_RELWITHDEBINFO;LLVM_LINK_LLVM_DYLIB;LLVM_INSTALL_UTILS;LLVM_VERSION_SUFFIX;LLVM_ENABLE_SPHINX;SPHINX_WARNINGS_AS_ERRORS;LLVM_BUILD_LLVM_DYLIB;LLVM_ENABLE_RTTI;LLVM_ENABLE_FFI;LIBCLANG_LIBRARY_VERSION;ENABLE_LINKER_BUILD_ID;POLLY_BUNDLED_JSONCPP;LLVM_EXPERIMENTAL_TARGETS_TO_BUILD;LLVM_USE_PERF;LLVM_ENABLE_ASSERTIONS;LLVM_BINUTILS_INCDIR;LLVM_HOST_TRIPLE;;LLVM_COMPILER_CHECKED;COMPILER_RT_BUILD_BUILTINS;LIBOMP_LIBFLAGS;CMAKE_SHARED_LINKER_FLAGS"