support Spectre mitigation patch for gcc compiler

1 files changed, 30 insertions, 0 deletions

diff --git a/configure b/configure
index 761cebc1e..80f66f8b3 100755
--- a/configure
+++ b/configure
@@ -646,6 +646,7 @@ EGREP
 GREP
 CPP
 HAVE_APPARMOR
+EXTRA_CFLAGS
 RANLIB
 INSTALL_DATA
 INSTALL_SCRIPT
@@ -3105,6 +3106,33 @@ else
 fi
 
 
+
+HAVE_SPECTRE="no"
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for Spectre mitigation support in gcc compiler" >&5
+$as_echo_n "checking for Spectre mitigation support in gcc compiler... " >&6; }
+if test "$CC" = "gcc"; then :
+
+        HAVE_SPECTRE="yes"
+        $CC -mindirect-branch=thunk -c dummy.c || HAVE_SPECTRE="no"
+        rm -f dummy.o
+
+fi
+if test "$HAVE_SPECTRE" = "yes"; then :
+
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+        EXTRA_CFLAGS+="-mindirect-branch=thunk"
+
+fi
+if test "$HAVE_SPECTRE" = "no"; then :
+
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: ... not available" >&5
+$as_echo "... not available" >&6; }
+
+fi
+
+
+
 HAVE_APPARMOR=""
 # Check whether --enable-apparmor was given.
 if test "${enable_apparmor+set}" = set; then :
@@ -5024,7 +5052,9 @@ echo "   file transfer support: $HAVE_FILE_TRANSFER"
 echo "   overlayfs support: $HAVE_OVERLAYFS"
 echo "   git install support: $HAVE_GIT_INSTALL"
 echo "   busybox workaround: $BUSYBOX_WORKAROUND"
+echo "   Spectre compiler patch: $HAVE_SPECTRE"
 echo "   EXTRA_LDFLAGS: $EXTRA_LDFLAGS"
+echo "   EXTRA_CFLAGS: $EXTRA_CFLAGS"
 echo "   fatal warnings: $HAVE_FATAL_WARNINGS"
 echo "   Gcov instrumentation: $HAVE_GCOV"
 echo "   Install contrib scripts: $HAVE_CONTRIB_INSTALL"