diff --git a/acinclude.m4 b/acinclude.m4
index f6a7852779..febb8961cc 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -1492,7 +1492,7 @@ AC_DEFUN([CURL_PREPARE_BUILDINFO], [
   if test "x$compiler_id" = 'xGNU_C'; then
     curl_pflags="${curl_pflags} GCC"
   fi
-  if "$compiler_id" = "APPLECLANG"; then
+  if test "$compiler_id" = "APPLECLANG"; then
     curl_pflags="${curl_pflags} APPLE-CLANG"
   elif test "$compiler_id" = "CLANG"; then
     curl_pflags="${curl_pflags} LLVM-CLANG"