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When using c++ exceptions, throw is calling terminate even through we can catch the exception. ARMv8m, arm none eabi 10.2.1 compiler.

Hello all, I have been struggling for quite a few days to get exceptions working on a new board. Some back story, the project I am working on has cpp and exceptions support. We are using llvm for cpp library and are using libsupc++.a from the toolchain. We have an armv7r based board on which exceptions are working. So, I can confirm that the llvm code is working fine. When I am trying to compile the same code for armv8m based board, if throw is called then it's resulting in calling terminate. Below are the flags used for compilation,

arm-none-eabi-g++ -c -fno-builtin -mcpu=cortex-m33 -mthumb -mcmse -mfloat-abi=soft -Wall -Wshadow -Wundef -g -Os -fno-strict-aliasing -fno-strength-reduce -fomit-frame-pointer -pipe -fcheck-new -frtti -std=c++17 -pedantic -ffunction-sections -fdata-sections -fexceptions main.cxx -o main.o

and below are the linker flags,

arm-none-eabi-ld --entry=__start -g --gc-sections -T script.ld -L"output/libraries" -L "/bin/../lib/gcc/arm-none-eabi/10.2.1/../../../../arm-none-eabi/lib/thumb/v8-m.main/nofp" -o "main_final" --start-group mylibs.a "/bin/../lib/gcc/arm-none-eabi/10.2.1/../../../../arm-none-eabi/lib/thumb/v8-m.main/nofp/libsupc++.a" "/bin/../lib/gcc/arm-none-eabi/10.2.1/thumb/v8-m.main/nofp/libgcc.a" --end-group -Map ./

and I have also placed the sections required for exceptions properly in the linker script,

/* Add This for C++ support */
.ARM.extab :
*(.ARM.extab* .gnu.linkonce.armextab.*)


.ARM.exidx :
__exidx_start = .;
*(.ARM.exidx* .gnu.linkonce.armexidx.*)
__exidx_end = .;

from the map file, it looks like the exidx start and end are placed properly. I have checked many forums regarding similar errors but none of them were helpful. (most of the resolutions were to modify the linker script, which is already correct in my case. Or to stop using lib nano. I am using libsupc++.a instead of libsupc++_nano.a)

So currently I am stuck without knowing how to proceed. 

Sample code I am using for test,

static void test_exception(void)
throw runtime_error("runtime error");

catch (runtime_error &e)
cout << "Catch exception: " << e.what() << endl;

I have also thought that the toolchain might be an issue. I was using a pretty old version of the toolchain (6.3.1). So I have also checked it with 10.2.1 but the same issue persists.

As far as I understand this can happen if the code is unable to find a suitable exception handler from the ARM.exidx section. But I don't know how to proceed on this hunch.

Also, I had to modify the libsupc++.a file a bit. I have removed the vterminate.o file from the library as it was causing issues during the call to terminate and have added my custom verbose_terminate function.

Any suggestions would be very helpful.