https://bugs.gentoo.org/753299
--- a/testsuite/lib/libffi.exp
+++ b/testsuite/lib/libffi.exp
@@ -287,9 +287,6 @@ proc libffi-init { args } {
     verbose "libffi $blddirffi"
 
     # Which compiler are we building with?
-    set tmp [grep "$blddirffi/config.log" "^ax_cv_c_compiler_vendor.*$"]
-    regexp -- {^[^=]*=(.*)$} $tmp nil compiler_vendor
-
     if { [string match $compiler_vendor "gnu"] } {
         set gccdir [lookfor_file $tool_root_dir gcc/libgcc.a]
         if {$gccdir != ""} {
--- a/configure.ac
+++ b/configure.ac
@@ -59,6 +59,7 @@ fi
 cat > local.exp <<EOF
 set CC_FOR_TARGET "$CC"
 set CXX_FOR_TARGET "$CXX"
+set compiler_vendor "$ax_cv_c_compiler_vendor"
 EOF
 
 AM_MAINTAINER_MODE
--- a/configure
+++ b/configure
@@ -17402,6 +17402,7 @@ fi
 cat > local.exp <<EOF
 set CC_FOR_TARGET "$CC"
 set CXX_FOR_TARGET "$CXX"
+set compiler_vendor "$ax_cv_c_compiler_vendor"
 EOF