diff --git a/configure.ac b/configure.ac
index 25a6f82f9..18e063154 100644
--- a/configure.ac
+++ b/configure.ac
@@ -370,7 +370,7 @@ AS_CASE([$ENABLED_FIPS],
         HAVE_FIPS_VERSION=5
         HAVE_FIPS_VERSION_MINOR=3
         ENABLED_FIPS="yes"
-	# for v5-dev, DEF_SP_MATH and DEF_FAST_MATH follow non-FIPS defaults (currently sp-math-all)
+        # for v5-dev, DEF_SP_MATH and DEF_FAST_MATH follow non-FIPS defaults (currently sp-math-all)
     ],
     [
         AC_MSG_ERROR([Invalid value for --enable-fips "$ENABLED_FIPS" (main options: v1, v2, v5, ready, dev, rand, no, disabled)])