Hi All, I am trying to understand the limitations (if any libgcc) has concerning embedded targets. In particular I am attempting to follow the instructions here: Freestanding Environments (Using the GNU Compiler Collection (GCC)) <https://gcc.gnu.org/onlinedocs/gcc/Freestanding-Environments.html> to obtain code coverage; I can compile, however I am seeing some linker errors like the following: ```bash /usr/bin/ld: /tmp/ccX2ca3G.ltrans0.ltrans.o:/edk2/OvmfPkg/EmuVariableFvbRuntimeDxe/FvbCov.c:83: undefined reference to `my_info' /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/12/libgcov.a(_gcov_info_to_gcda.o): in function `__gcov_info_to_gcda': (.text+0x31d): undefined reference to `mmap' /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/12/libgcov.a(_gcov_info_to_gcda.o): in function `__gcov_info_to_gcda.cold': (.text.unlikely+0x1): undefined reference to `abort' /usr/bin/ld: warning: creating DT_TEXTREL in a PIE collect2: error: ld returned 1 exit status ``` My environment lacks any standard lib and I have the following compiler/linker options: compiler ```bash INFO - "gcc" -MMD -MF /edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/OUTPUT/FvbCov.obj.deps -g -Os -fshort-wchar -fno-builtin -fno-strict-aliasing -Wall -Werror -Wno-array-bounds -include AutoGen.h -fno-common -ffunction-sections -fdata-sections -DSTRING_ARRAY_NAME=EmuVariableFvbRuntimeDxeStrings -m64 -fno-stack-protector "-DEFIAPI=__attribute__((ms_abi))" -maccumulate-outgoing-args -mno-red-zone -Wno-address -mcmodel=small -fpie -fno-asynchronous-unwind-tables -Wno-address -flto -DUSING_LTO -Os -coverage -mno-mmx -mno-sse -D DISABLE_NEW_DEPRECATED_INTERFACES -D ENABLE_MD5_DEPRECATED_INTERFACES -c -o /edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/OUTPUT/./FvbCov.obj -I/edk2/OvmfPkg/EmuVariableFvbRuntimeDxe -I/edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/DEBUG -I/edk2/MdePkg -I/edk2/MdePkg/Include -I/edk2/MdePkg/Test/UnitTest/Include -I/edk2/MdePkg/Include/X64 -I/edk2/MdeModulePkg -I/edk2/MdeModulePkg/Include -I/edk2/OvmfPkg -I/edk2/OvmfPkg/Include -I/edk2/OvmfPkg/Csm/Include /edk2/OvmfPkg/EmuVariableFvbRuntimeDxe/FvbCov.c ``` linker ```bash "gcc" -o /edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/DEBUG/EmuVariableFvbRuntimeDxe.dll -nostdlib -Wl,-n,-q,--gc-sections -z common-page-size=0x40 -Wl,--entry,_ModuleEntryPoint -u _ModuleEntryPoint -Wl,-Map,/edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/DEBUG/EmuVariableFvbRuntimeDxe.map,--whole-archive -Wl,-melf_x86_64,--oformat=elf64-x86-64,-pie -flto -Os -fprofile-arcs -ftest-coverage -fprofile-info-section -z common-page-size=0x1000 -Wl,--start-group,@/edk2/Build/Ovmf3264/DEBUG_GCC5/X64/OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb/OUTPUT/static_library_files.lst,--end-group -g -Os -fshort-wchar -fno-builtin -fno-strict-aliasing -Wall -Werror -Wno-array-bounds -include AutoGen.h -fno-common -ffunction-sections -fdata-sections -DSTRING_ARRAY_NAME=EmuVariableFvbRuntimeDxeStrings -m64 -fno-stack-protector "-DEFIAPI=__attribute__((ms_abi))" -maccumulate-outgoing-args -mno-red-zone -Wno-address -mcmodel=small -fpie -fno-asynchronous-unwind-tables -Wno-address -flto -DUSING_LTO -Os -coverage -mno-mmx -mno-sse -D DISABLE_NEW_DEPRECATED_INTERFACES -D ENABLE_MD5_DEPRECATED_INTERFACES -Wl,--defsym=PECOFF_HEADER_SIZE=0x228 -Wl,--script=/edk2/BaseTools/Scripts/GccBase.lds -Wno-error ``` Let me know if there are additional info, in the meantime I will create a more minimal build environment to try and narrow down the possibilities. Thank you :)
