BaseTools IA32/X64: prevent .eh_frame sections from being generated

After the recent GNU linker script changes, the following warning is
emitted many times during the OVMF build:

BFD: <...>: warning: Empty loadable segment detected, is this intentional ?

This is caused by the fact that, now that the section layout has changed
somewhat, the .eh_frame section is assigned an ELF segment of its own,
which ends up with no contents at all after we strip the .eh_frame
section from the output. (Note that the program headers that contain the
segment information are completely irrelevant to us since the PE/COFF
conversion does not rely on them.)

Since we only retain the .eh_frame data for external debugging, and not
for things like stack unwinding or generating backtraces at runtime, we
can remedy the situation by passing -fno-asynchronous-unwind-tables on
the GCC command line. This option instructs the compiler to emit the
unwind data into a debug section called .debug_frame instead of into
.eh_frame.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Build-tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18217 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/BaseTools/Conf/tools_def.template b/BaseTools/Conf/tools_def.template
index 6e2d4909b9fc5d0bb2bf438020bb4a6206de9942..859fbe14ad597803634e0b33a409629b77c4d5ae 100644 (file)
--- a/BaseTools/Conf/tools_def.template
+++ b/BaseTools/Conf/tools_def.template
@@ -3839,8 +3839,8 @@ DEFINE GCC_ARM_RC_FLAGS            = -I binary -O elf32-littlearm     -B arm
 DEFINE GCC_AARCH64_RC_FLAGS        = -I binary -O elf64-littleaarch64 -B aarch64 --rename-section .data=.hii\r
 \r
 DEFINE GCC44_ALL_CC_FLAGS            = -g -fshort-wchar -fno-strict-aliasing -Wall -Werror -Wno-array-bounds -ffunction-sections -fdata-sections -c -include AutoGen.h -DSTRING_ARRAY_NAME=$(BASE_NAME)Strings\r
-DEFINE GCC44_IA32_CC_FLAGS           = DEF(GCC44_ALL_CC_FLAGS) -m32 -malign-double -fno-stack-protector -D EFI32\r
-DEFINE GCC44_X64_CC_FLAGS            = DEF(GCC44_ALL_CC_FLAGS) -m64 -fno-stack-protector "-DEFIAPI=__attribute__((ms_abi))" -DNO_BUILTIN_VA_FUNCS -mno-red-zone -Wno-address -mcmodel=large\r
+DEFINE GCC44_IA32_CC_FLAGS           = DEF(GCC44_ALL_CC_FLAGS) -m32 -malign-double -fno-stack-protector -D EFI32 -fno-asynchronous-unwind-tables\r
+DEFINE GCC44_X64_CC_FLAGS            = DEF(GCC44_ALL_CC_FLAGS) -m64 -fno-stack-protector "-DEFIAPI=__attribute__((ms_abi))" -DNO_BUILTIN_VA_FUNCS -mno-red-zone -Wno-address -mcmodel=large -fno-asynchronous-unwind-tables\r
 DEFINE GCC44_IA32_X64_DLINK_COMMON   = -nostdlib -n -q --gc-sections -z common-page-size=0x20\r
 DEFINE GCC44_IA32_X64_ASLDLINK_FLAGS = DEF(GCC44_IA32_X64_DLINK_COMMON) --entry ReferenceAcpiTable -u ReferenceAcpiTable\r
 DEFINE GCC44_IA32_X64_DLINK_FLAGS    = DEF(GCC44_IA32_X64_DLINK_COMMON) --entry $(IMAGE_ENTRY_POINT) -u $(IMAGE_ENTRY_POINT) -Map $(DEST_DIR_DEBUG)/$(BASE_NAME).map\r