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
This commit is contained in:
Ard Biesheuvel 2015-08-13 06:02:00 +00:00 committed by abiesheuvel
parent ed5d1532f9
commit 26ecc55c02
1 changed files with 2 additions and 2 deletions

View File

@ -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
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
DEFINE GCC44_IA32_CC_FLAGS = DEF(GCC44_ALL_CC_FLAGS) -m32 -malign-double -fno-stack-protector -D EFI32
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
DEFINE GCC44_IA32_CC_FLAGS = DEF(GCC44_ALL_CC_FLAGS) -m32 -malign-double -fno-stack-protector -D EFI32 -fno-asynchronous-unwind-tables
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
DEFINE GCC44_IA32_X64_DLINK_COMMON = -nostdlib -n -q --gc-sections -z common-page-size=0x20
DEFINE GCC44_IA32_X64_ASLDLINK_FLAGS = DEF(GCC44_IA32_X64_DLINK_COMMON) --entry ReferenceAcpiTable -u ReferenceAcpiTable
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