Commit: patch 9.1.1642: configure: wrong C99 feature test

[Christian Brabandt]

patch 9.1.1642: configure: wrong C99 feature test

Commit: https://github.com/vim/vim/commit/0ebe55af548e5347fc1e4119e20d5063d17f62d3
Author: Damien Lejay <dam...@lejay.be>
Date: Sun Aug 17 21:05:40 2025 +0200

patch 9.1.1642: configure: wrong C99 feature test

Problem: configure: wrong C99 feature test
Solution: Update inverted C99 feature test logic
(Damien Lejay)

closes: #18024

Signed-off-by: Damien Lejay <dam...@lejay.be>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/auto/configure b/src/auto/configure
index 5f7559247..d3d72cd16 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
" "$as_me:${as_lineno-$LINENO}: checking for unsigned long long int" >&5
diff --git a/src/configure.ac b/src/configure.ac
index 9016f9699..4544f46f5 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -30,7 +30,7 @@ if test -z "$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 610114d6d..a4d934706 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,
/**/