diff -ur ../1/libcc1/Makefile.am ./libcc1/Makefile.am
--- ../1/libcc1/Makefile.am	2018-06-12 19:23:46.000000000 +0200
+++ ./libcc1/Makefile.am	2018-09-15 22:02:50.670937188 +0200
@@ -37,8 +37,8 @@
 	    $(Wc)$(libiberty_normal)))
 libiberty_dep = $(patsubst $(Wc)%,%,$(libiberty))
 
-plugindir = $(libdir)/gcc/$(target_noncanonical)/$(gcc_version)/plugin
-cc1libdir = $(libdir)/$(libsuffix)
+cc1libdir = $(libexecdir)/gcc/$(target_noncanonical)/$(gcc_version)
+plugindir = $(cc1libdir)
 
 if ENABLE_PLUGIN
 plugin_LTLIBRARIES = libcc1plugin.la libcp1plugin.la
Only in ./libcc1: Makefile.am.orig
diff -ur ../1/libcc1/Makefile.in ./libcc1/Makefile.in
--- ../1/libcc1/Makefile.in	2018-06-12 19:23:46.000000000 +0200
+++ ./libcc1/Makefile.in	2018-09-15 22:02:21.667644486 +0200
@@ -303,8 +303,8 @@
 	    $(Wc)$(libiberty_normal)))
 
 libiberty_dep = $(patsubst $(Wc)%,%,$(libiberty))
-plugindir = $(libdir)/gcc/$(target_noncanonical)/$(gcc_version)/plugin
-cc1libdir = $(libdir)/$(libsuffix)
+cc1libdir = $(libexecdir)/gcc/$(target_noncanonical)/$(gcc_version)
+plugindir = $(cc1libdir)
 @ENABLE_PLUGIN_TRUE@plugin_LTLIBRARIES = libcc1plugin.la libcp1plugin.la
 @ENABLE_PLUGIN_TRUE@cc1lib_LTLIBRARIES = libcc1.la
 BUILT_SOURCES = c-compiler-name.h cp-compiler-name.h