Hi,

I think the GNU objdump prints out the build attributes, in a GNU elf file this section looks like this:

readelf -A tests_reg/spe/build2/bin/tfm_s.elf

Attribute Section: aeabi

File Attributes

Tag_CPU_name: "cortex-m85"

Tag_CPU_arch: v8.1-M.mainline

Tag_CPU_arch_profile: Microcontroller

Tag_THUMB_ISA_use: Yes

Tag_ABI_PCS_wchar_t: 4

Tag_ABI_FP_denormal: Needed

Tag_ABI_FP_exceptions: Needed

Tag_ABI_FP_number_model: IEEE 754

Tag_ABI_align_needed: 8-byte

Tag_ABI_enum_size: small

Tag_CPU_unaligned_access: v6

Tag_DSP_extension: Allowed

Tag_PAC_extension: PAC/AUT instructions permitted in the NOP and in the non-NOP space

Tag_BTI_extension: BTI instructions permitted in the NOP and in the non-NOP space

If we build with armclang, these attributes are not included in the elf file (no aeabi attributes section, this is an optional/implementation defined section), but included in every object file, so the linker can check the compatibility between each object file (FP, abi, etc).

I’ve checked both GNU and armclang builds, the ELF file headers are the same which contains the arm 32bit architecture information too.

Can I ask what problems are you facing?

You can try using debug build or you can give this armlink option a try:
https://developer.arm.com/documentation/101754/0622/armlink-Reference/armlink-Command-line-Options/--elf-output-format

Regards,
Dávid

From: Roman.Mazurak--- via TF-M <tf-m@lists.trustedfirmware.org>
Sent: Wednesday, August 14, 2024 12:53 PM
To: tf-m@lists.trustedfirmware.org
Subject: [TF-M] ARMCLANG generates ELF with armv3m architecture

Hello,

We noticed that build of TF-M for CM33 platform generates ELF file for which architecture is armv3m. Step to reproduce:

Build TF-M secure image for CM33 platform with armclang (used 6.19).
Use arm-none-eabi-objdump provided with arm-gnu-toolchain-11.3.rel1-mingw-w64-i686-arm-none-eabi to print headers:

arm-none-eabi-objdump -x tfm_s.axf

You will see following output:

tfm_s.axf

architecture: armv3m, flags 0x00000012:

EXEC_P, HAS_SYMS

While fromelf (from armclang) prints following:

========================================================================

** ELF Header Information

File Name: tfm_s.axf

Machine class: ELFCLASS32 (32-bit)

Data encoding: ELFDATA2LSB (Little endian)

Header version: EV_CURRENT (Current version)

Operating System ABI: none

ABI Version: 0

File Type: ET_EXEC (Executable) (2)

Machine: EM_ARM (ARM)

Image Entry point: 0x16004319

Flags: EF_ARM_HASENTRY + EF_ARM_ABI_FLOAT_HARD (0x05000402)

ARM ELF revision: 5 (ABI version 2)

Is’t expected? Because we have problems with debugging images generated by armclang in eclipse with gdb.

Regards,

Roman.