why gcc won't support FDPIC in thumb mode? I'm trying to build a toolchain for my mmu-less cortex m7 cpu that is running the latest release of the mainline linux kernel using crosstool-ng. I've set the instruction-set to thumb because cortex m doesn't support ARM ISA (it's a thumb only processor). because I use shared libraries, I need FDPIC ELF instead of flat BFLT executables. so, I choosed FDPIC in the crosstool-ng configuration menuconfig. when I build the toolchain, it throws a very strange error. cc1: sorry, unimplemented: FDPIC mode is not supported in Thumb-1 mode I'm so confused! FDPIC ELF format is mainly designed for mmu-less architectures such as cortex-m and cortex-r that are thumb only processors. so why it is saying that FDPIC mode is not supported in Thumb-1 mode? Even I've set -mcpu=cortex-m7 and -march=armv7e-m in my toolchain configuration but still I see the error. these are some useful sources about fdpic format on ARM MCUs: https://static.linaro.org/connect/sfo15/Presentations/09-24-Thursday/SFO15-406-%20ARM%20FDPIC%20Toolchains.pdf https://gcc.gnu.org/legacy-ml/gcc-patches/2019-09/msg00098.html https://gcc.gnu.org/legacy-ml/gcc-patches/2019-09/msg00533.html https://www.google.com/url?sa=t&source=web&rct=j&url=https://ntnuopen.ntnu.no/ntnu-xmlui/bitstream/handle/11250/250748/347817_FULLTEXT01.pdf%3Fsequence%3D3&ved=2ahUKEwiztaiqgMbyAhUFwKQKHeeGAGQ4ChAWegQIHRAB&usg=AOvVaw3SLe1u323I7JjkoqBipoXH Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows
