diff --git a/src/auto/configure b/src/auto/configure
index 5f75592470..d3d72cd165 100755
--- a/src/auto/configure
+++ b/src/auto/configure
@@ -4640,7 +4640,7 @@ fi
 
 fi
 
-if test x"$ac_cv_prog_cc_c99" != xno; then
+if test x"$ac_cv_prog_cc_c99" = xno; then
 
 
   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for unsigned long long int" >&5
diff --git a/src/configure.ac b/src/configure.ac
index 9016f96993..4544f46f58 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -30,7 +30,7 @@ if test -z "$PKG_CONFIG"; then
 fi
 
 dnl Check that the C99 features that Vim uses are supported:
-if test x"$ac_cv_prog_cc_c99" != xno; then
+if test x"$ac_cv_prog_cc_c99" = xno; then
   dnl If the compiler doesn't explicitly support C99, then check
   dnl for the specific features Vim uses
 
@@ -2408,7 +2408,7 @@ AC_MSG_CHECKING(--with-wayland argument)
 AC_ARG_WITH(wayland,
 	[  --with-wayland	  Include support for the Wayland protocol.],
 	[with_wayland=$withval],
-	AS_IF([test "x$features" = xtiny], 
+	AS_IF([test "x$features" = xtiny],
 			[with_wayland=no
 			 AC_MSG_RESULT([cannot use wayland with tiny features])],
 			[with_wayland=yes
diff --git a/src/version.c b/src/version.c
index 610114d6d7..a4d934706d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -719,6 +719,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1642,
 /**/
     1641,
 /**/