This is mandatory on ARM64EC and also required on AArch64 for ARM64X
builds.
Instead of extending the existing logic, unify it by always including
it in mingwex.
Fill CF Guard fields with zeroes when CF Guard is not enabled in CRT
builds. This
leverages existing LLD load config validation warnings to signal
potential issues
if the user enables CF Guard while using a CRT that was not built
with it.
In practice, this means load config will always be present in output
images when using
LLD. Since ld.bfd does not support load config, it remains unaffected.
---
mingw-w64-crt/Makefile.am | 8 ++---
mingw-w64-crt/configure.ac | 4 +--
.../mingw_cfguard_loadcfg.S => crt/loadcfg.S} | 30 +++++++++++++------
3 files changed, 24 insertions(+), 18 deletions(-)
rename mingw-w64-crt/{cfguard/mingw_cfguard_loadcfg.S =>
crt/loadcfg.S} (82%)
diff --git a/mingw-w64-crt/Makefile.am b/mingw-w64-crt/Makefile.am
index 423e233ac..186e17979 100644
--- a/mingw-w64-crt/Makefile.am
+++ b/mingw-w64-crt/Makefile.am
@@ -22,6 +22,7 @@ endif
AM_CPPFLAGS=$(sysincludes)
AM_CFLAGS=-pipe -std=gnu99 -D_CRTBLD -D_WIN32_WINNT=0x0f00
-D__MSVCRT_VERSION__=0x600 -D__USE_MINGW_ANSI_STDIO=0
@IMAGEBASE_CFLAGS@ @CFGUARD_CFLAGS@ @ADD_C_CXX_WARNING_FLAGS@
@ADD_C_ONLY_WARNING_FLAGS@
AM_CXXFLAGS=@ADD_C_CXX_WARNING_FLAGS@ @ADD_CXX_ONLY_WARNING_FLAGS@
+AM_CCASFLAGS=@CFGUARD_CFLAGS@
CPPFLAGSARM32=-mfpu=vfpv3
CPPFLAGS32=-m32 -masm=att
CPPFLAGS64=-m64 -masm=att
@@ -928,6 +929,7 @@ src_msvcr120_app=\
# These mingwex sources are target independent:
src_libmingwex=\
+ crt/loadcfg.S \
cfguard/mingw_cfguard_support.c \
\
misc/dllmain.c \
@@ -1015,12 +1017,6 @@ src_libmingwex=\
stdio/vsnprintf.c stdio/vsnwprintf.c \
stdio/wtoll.c stdio/mingw_asprintf.c
stdio/mingw_vasprintf.c
-# Include the default load config struct only for Control Flow Guard
support.
-if CFGUARD
-src_libmingwex+=\
- cfguard/mingw_cfguard_loadcfg.S
-endif
-
# these go into both 32 and 64 bit x86 versions:
src_libmingwex_x86=\
math/cbrtl.c math/erfl.c math/fdiml.c
math/fmal.c math/fmaxl.c \
diff --git a/mingw-w64-crt/configure.ac b/mingw-w64-crt/configure.ac
index 37851f605..f4f8d954d 100644
--- a/mingw-w64-crt/configure.ac
+++ b/mingw-w64-crt/configure.ac
@@ -273,10 +273,8 @@ AC_ARG_ENABLE([cfguard],
AC_MSG_RESULT([$enable_cfguard])
AS_CASE([$enable_cfguard],
[no],[],
- [yes],[AS_VAR_SET([CFGUARD])
- AS_VAR_SET([CFGUARD_CFLAGS],[-mguard=cf])],
+ [yes],[AS_VAR_SET([CFGUARD_CFLAGS],["-mguard=cf -DHAS_CFGUARD"])],
[AC_MSG_ERROR([invalid argument. Must be either yes or no.])])
-AM_CONDITIONAL([CFGUARD], [AS_VAR_TEST_SET([CFGUARD])])
AC_SUBST([CFGUARD_CFLAGS])
AC_MSG_CHECKING([whether to enable experimental features])
diff --git a/mingw-w64-crt/cfguard/mingw_cfguard_loadcfg.S
b/mingw-w64-crt/crt/loadcfg.S
similarity index 82%
rename from mingw-w64-crt/cfguard/mingw_cfguard_loadcfg.S
rename to mingw-w64-crt/crt/loadcfg.S
index a7028b1a8..ab445d708 100644
--- a/mingw-w64-crt/cfguard/mingw_cfguard_loadcfg.S
+++ b/mingw-w64-crt/crt/loadcfg.S
@@ -13,6 +13,12 @@ Many of the symbols referenced here are supplied
by the linker. This file has
been constructed with LLVM/LLD in mind.
*/
+#ifdef HAS_CFGUARD
+ .def @feat.00; .scl 3; .type 0; .endef
+ .globl @feat.00
+@feat.00 = 0x800
+#endif
+
