diff --git a/ares/m4/cares-compilers.m4 b/ares/m4/cares-compilers.m4
index 8af70637b5..67bc904ba5 100644
--- a/ares/m4/cares-compilers.m4
+++ b/ares/m4/cares-compilers.m4
@@ -557,5 +557,5 @@ AC_DEFUN([CARES_VAR_STRIP], [
     fi
   done
   dnl squeeze whitespace out of result
-  [$1]=`eval echo $[$1]`
+  [$1]=`eval echo $ac_var_stripped`
 ])
diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4
index 1cff5be010..90890700fb 100644
--- a/m4/curl-compilers.m4
+++ b/m4/curl-compilers.m4
@@ -549,5 +549,5 @@ AC_DEFUN([CURL_VAR_STRIP], [
     fi
   done
   dnl squeeze whitespace out of result
-  [$1]=`eval echo $[$1]`
+  [$1]=`eval echo $ac_var_stripped`
 ])