diff --git a/autoconf/configure.ac b/autoconf/configure.ac
index fb73e51df3f0..a3cb05c44dc6 100644
--- a/autoconf/configure.ac
+++ b/autoconf/configure.ac
@@ -74,7 +74,7 @@ if test ${srcdir} != "." ; then
 fi
 
 dnl Quit if it is an in-source build
-if test ${srcdir} == "." ; then
+if test ${srcdir} = "." ; then
   AC_MSG_ERROR([In-source builds are not allowed. Please configure from a separate build directory!])
 fi
 
diff --git a/configure b/configure
index c895057ab07d..5b15d122c07d 100755
--- a/configure
+++ b/configure
@@ -2033,7 +2033,7 @@ echo "$as_me: error: Already configured in ${srcdir}" >&2;}
   fi
 fi
 
-if test ${srcdir} == "." ; then
+if test ${srcdir} = "." ; then
   { { echo "$as_me:$LINENO: error: In-source builds are not allowed. Please configure from a separate build directory!" >&5
 echo "$as_me: error: In-source builds are not allowed. Please configure from a separate build directory!" >&2;}
    { (exit 1); exit 1; }; }