I'm trying to compile my program to armv6, but the ELF file is built for armv7, even when I use -march=armv6 option. All .o files has been compiled to armv6, only the ELF file is wrong.
Basically I'm compiling like this:
arm-linux-gnueabihf-g++ -static -march=armv6 -mfpu=vfp -mfloat-abi=hard -marm -Wa,-march=armv6 -o "Bridge"
Checking all .o files I get this:
$ readelf -a -W Bridge.o | grep Tag Tag_CPU_name: "6" Tag_CPU_arch: v6 Tag_ARM_ISA_use: Yes Tag_THUMB_ISA_use: Thumb-1 Tag_FP_arch: VFPv2 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_align_preserved: 8-byte, except leaf SP Tag_ABI_enum_size: int Tag_ABI_VFP_args: VFP registers Tag_ABI_optimization_goals: Aggressive Speed Tag_CPU_unaligned_access: v6
But checking the ELF file:
$ readelf -a -W Bridge | grep Tag Tag_CPU_name: "7-A" Tag_CPU_arch: v7 Tag_CPU_arch_profile: Application Tag_ARM_ISA_use: Yes Tag_THUMB_ISA_use: Thumb-2 Tag_FP_arch: VFPv3 Tag_Advanced_SIMD_arch: NEONv1 Tag_ABI_PCS_wchar_t: 4 Tag_ABI_FP_rounding: Needed 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_align_preserved: 8-byte, except leaf SP Tag_ABI_enum_size: int Tag_ABI_VFP_args: VFP registers Tag_CPU_unaligned_access: v6
I'm using Linaro GCC 7.2.1, and I've also tried with old versions, and different compilation flags combinations. Can someone tell me how to compile an armv6 ELF file?