make/autoconf/flags-cflags.m4

*** 762,771 ****
--- 762,798 ----
      $1_TOOLCHAIN_CFLAGS="${$1_GCC6_CFLAGS}"
  
      $1_WARNING_CFLAGS_JVM="-Wno-format-zero-length -Wtype-limits -Wuninitialized"
    fi
  
+   case $TOOLCHAIN_TYPE in
+     gcc)
+       $2NO_SPECULATIVE_CTI_CFLAGS="-mindirect-branch=thunk \
+           -mfunction-return=thunk -mindirect-branch-register"
+       ;;
+     microsoft)
+       $2NO_SPECULATIVE_CTI_CFLAGS="-Qspectre"
+       ;;
+     *)
+       $2NO_SPECULATIVE_CTI_CFLAGS=""
+       ;;
+   esac
+   if test -n "${$2NO_SPECULATIVE_CTI_CFLAGS}"; then
+     FLAGS_COMPILER_CHECK_ARGUMENTS(ARGUMENT: [${$2NO_SPECULATIVE_CTI_CFLAGS}],
+         IF_FALSE: [
+           AC_MSG_WARN([Speculative call mitigations not available with compiler version])
+           $2NO_SPECULATIVE_CTI_CFLAGS=""
+         ]
+     )
+   fi
+   AC_MSG_CHECKING([for speculative calls mitigation flags for $1])
+   if test -n "${$2NO_SPECULATIVE_CTI_CFLAGS}"; then
+     AC_MSG_RESULT(${$2NO_SPECULATIVE_CTI_CFLAGS})
+   else
+     AC_MSG_RESULT(no)
+   fi
+ 
    # EXPORT to API
    CFLAGS_JVM_COMMON="$ALWAYS_CFLAGS_JVM $ALWAYS_DEFINES_JVM $TOOLCHAIN_CFLAGS_JVM \
        $OS_CFLAGS $OS_CFLAGS_JVM $CFLAGS_OS_DEF_JVM $DEBUG_CFLAGS_JVM \
        $WARNING_CFLAGS $WARNING_CFLAGS_JVM $JVM_PICFLAG"
  
*** 780,791 ****
    CFLAGS_JDK_COMMON_CONLY="$TOOLCHAIN_CFLAGS_JDK_CONLY  \
        $WARNING_CFLAGS_JDK_CONLY ${$2EXTRA_CFLAGS}"
    CFLAGS_JDK_COMMON_CXXONLY="$ALWAYS_DEFINES_JDK_CXXONLY $TOOLCHAIN_CFLAGS_JDK_CXXONLY \
        $WARNING_CFLAGS_JDK_CXXONLY ${$2EXTRA_CXXFLAGS}"
  
!   $1_CFLAGS_JVM="${$1_DEFINES_CPU_JVM} ${$1_CFLAGS_CPU} ${$1_CFLAGS_CPU_JVM} ${$1_TOOLCHAIN_CFLAGS} ${$1_WARNING_CFLAGS_JVM}"
!   $1_CFLAGS_JDK="${$1_DEFINES_CPU_JDK} ${$1_CFLAGS_CPU} ${$1_CFLAGS_CPU_JDK} ${$1_TOOLCHAIN_CFLAGS}"
  
    $2JVM_CFLAGS="$CFLAGS_JVM_COMMON ${$1_CFLAGS_JVM} ${$2EXTRA_CXXFLAGS}"
  
    $2CFLAGS_JDKEXE="$CFLAGS_JDK_COMMON $CFLAGS_JDK_COMMON_CONLY ${$1_CFLAGS_JDK}"
    $2CXXFLAGS_JDKEXE="$CFLAGS_JDK_COMMON $CFLAGS_JDK_COMMON_CXXONLY ${$1_CFLAGS_JDK}"
--- 807,822 ----
    CFLAGS_JDK_COMMON_CONLY="$TOOLCHAIN_CFLAGS_JDK_CONLY  \
        $WARNING_CFLAGS_JDK_CONLY ${$2EXTRA_CFLAGS}"
    CFLAGS_JDK_COMMON_CXXONLY="$ALWAYS_DEFINES_JDK_CXXONLY $TOOLCHAIN_CFLAGS_JDK_CXXONLY \
        $WARNING_CFLAGS_JDK_CXXONLY ${$2EXTRA_CXXFLAGS}"
  
!   # The jdk libraries always use the speculative calls mitigations, while it's
!   # optional for the JVM.
!   $1_CFLAGS_JVM="${$1_DEFINES_CPU_JVM} ${$1_CFLAGS_CPU} ${$1_CFLAGS_CPU_JVM} \
!       ${$1_TOOLCHAIN_CFLAGS} ${$1_WARNING_CFLAGS_JVM}"
!   $1_CFLAGS_JDK="${$1_DEFINES_CPU_JDK} ${$1_CFLAGS_CPU} ${$1_CFLAGS_CPU_JDK} \
!       ${$1_TOOLCHAIN_CFLAGS} ${$2NO_SPECULATIVE_CTI_CFLAGS}"
  
    $2JVM_CFLAGS="$CFLAGS_JVM_COMMON ${$1_CFLAGS_JVM} ${$2EXTRA_CXXFLAGS}"
  
    $2CFLAGS_JDKEXE="$CFLAGS_JDK_COMMON $CFLAGS_JDK_COMMON_CONLY ${$1_CFLAGS_JDK}"
    $2CXXFLAGS_JDKEXE="$CFLAGS_JDK_COMMON $CFLAGS_JDK_COMMON_CXXONLY ${$1_CFLAGS_JDK}"
*** 795,804 ****
--- 826,836 ----
    AC_SUBST($2JVM_CFLAGS)
    AC_SUBST($2CFLAGS_JDKLIB)
    AC_SUBST($2CFLAGS_JDKEXE)
    AC_SUBST($2CXXFLAGS_JDKLIB)
    AC_SUBST($2CXXFLAGS_JDKEXE)
+   AC_SUBST($2NO_SPECULATIVE_CTI_CFLAGS)
  ])
  
  # FLAGS_SETUP_GCC6_COMPILER_FLAGS([PREFIX])
  # Arguments:
  # $1 - Prefix for each variable defined.