diff --git a/Sanity/upstream-scripttests/runtest.sh b/Sanity/upstream-scripttests/runtest.sh
index 8caa7ef..1d3bb78 100755
--- a/Sanity/upstream-scripttests/runtest.sh
+++ b/Sanity/upstream-scripttests/runtest.sh
@@ -104,9 +104,17 @@ rlJournalStart
         rlRun "RUBY_CFLAGS='`ruby -r rbconfig -e "puts RbConfig::CONFIG['CFLAGS']"`'" 0 "Get ruby CFLAGS"
         rlRun "export CFLAGS='$RUBY_CFLAGS'"                                          0 "Set ruby CFLAGS"
         
+        # Centos Stream 11 and Fedora 42+ defaults to C23 standard, Vim currently does not work with it
+        # https://github.com/vim/vim/issues/16575 - set the older standard
+        if rlIsRHELLike '>10' || rlIsFedora '>=42'
+        then
+            rlRun "export STD_FLAG='-std=c17'"
+        fi
+
         # show relevant info & ENV variables
         rlLog "TEST:           $TEST"
         rlLog "CONFOPT:        $CONFOPT"
+        rlLog "STD_FLAG:       $STD_FLAG"
         rlLog "TERM (default): $TERM"
         rlLog "TERM (testing): $TERM_type"
         rlRun -l  "vim --version"
@@ -134,7 +142,7 @@ rlJournalStart
         rlRun "TERM=$TERM_type"
 
         # following block of code is taken from upstream travis.yml
-        rlRun "su $TESTER -c './configure ${CONFOPT} CFLAGS=\"${CFLAGS} $RUBY_FLAGS -std=c17\"'" 0 "Configure Vim"
+        rlRun "su $TESTER -c './configure ${CONFOPT} CFLAGS=\"${CFLAGS} ${RUBY_FLAGS} ${STD_FLAG}\" $RPM_WORKAROUND'" 0 "Configure Vim"
         rlRun "su $TESTER -c 'make'" 0 "Build the binary which we substitute"
         rlRun "su $TESTER -c 'ln -sf /usr/bin/vim  src/vim'"    0   "Create symlink to installed vim for testing"
         rlRun "su $TESTER -c 'TERM=$TERM_type make ${TEST} |& tee output_main'" 0,2 "Run tests (skip builtin terminal errors)"
diff --git a/Sanity/upstream-unittests/runtest.sh b/Sanity/upstream-unittests/runtest.sh
index bf49a7b..81f439e 100755
--- a/Sanity/upstream-unittests/runtest.sh
+++ b/Sanity/upstream-unittests/runtest.sh
@@ -80,9 +80,17 @@ rlJournalStart
         # we need to set several env variable randomly to get configure working again...
         rlRun "RPM_WORKAROUND='RPM_ARCH=\"x86_64\" RPM_PACKAGE_RELEASE=\"1\" RPM_PACKAGE_VERSION=\"1\" RPM_PACKAGE_NAME=\"vim\"'"
 
+        # Centos Stream 11 and Fedora 42+ defaults to C23 standard, Vim currently does not work with it
+        # https://github.com/vim/vim/issues/16575 - set the older standard
+        if rlIsRHELLike '>10' || rlIsFedora '>=42'
+        then
+            rlRun "export STD_FLAG='-std=c17'"
+        fi
+
         # show relevant info & ENV variables
         rlLog "TEST:           $TEST"
         rlLog "CONFOPT:        $CONFOPT"
+        rlLog "STD_FLAG:       $STD_FLAG"
         rlLog "FEATURES:       $FEATURES"
         rlLog "TERM (default): $TERM"
         rlLog "TERM (testing): $TERM_type"
@@ -95,7 +103,7 @@ rlJournalStart
         rlRun "TERM=$TERM_type"
 
         # following block of code is taken from upstream travis.yml
-        rlRun "su $TESTER -c './configure ${CONFOPT} CFLAGS=\"${CFLAGS} $RUBY_FLAGS -std=c17\" $RPM_WORKAROUND'" 0 "Configure Vim"
+        rlRun "su $TESTER -c './configure ${CONFOPT} CFLAGS=\"${CFLAGS} ${RUBY_FLAGS} ${STD_FLAG}\" $RPM_WORKAROUND'" 0 "Configure Vim"
         rlRun "su $TESTER -c '$RPM_WORKAROUND make'" 0 "Build the binary which we substitute"
         rlRun "su $TESTER -c 'ln -sf /usr/bin/vim  src/vim'"    0   "Create symlink to installed vim for testing"
         rlRun "su $TESTER -c 'make ${TEST} |& tee output'" 0,2 "Run tests (skip builtin terminal errors)"