[llvm-dev] How to force address of symbol

[Vicente Bergas via llvm-dev]

Hello,
i would like to force the address of the symbol "start" which is a function.
(there is also the use case where the symbol of interest is a data array)
The symbol is declared in file test.c:
__asm__ (
  "  .section .test         \n"
  "  .global start          \n"
  "  .syntax unified        \n"
  "  .thumb                 \n"
  "  .thumb_func            \n"
  "  .type start, %function \n"
  "start:                   \n"
  "    ldr r0, stack_addr   \n"
  "    mov sp, r0           \n"
  "    b   reset            \n"
  "  .align 2               \n"
  "stack_addr:              \n"
  "  .word stack            \n"
);
void reset(void) { while (1); }

and compiled this way:
clang --target=armv6-m -mfloat-abi=soft -c test.c -o test.o
or
${CROSS_COMPILE}gcc -c test.c -o test.o

When linking i am using the script file link.ld:
MEMORY { RAM (rwx) : ORIGIN = 0x1000, LENGTH = 0x1000 }
ENTRY(start)
SECTIONS {
  .text : { *(.test) } > RAM
  stack = ORIGIN(RAM) + LENGTH(RAM);
}

and linked this way:
ld.lld -T link.ld test.o --gc-sections -o test.elf
or
${CROSS_COMPILE}ld -T link.ld test.o --gc-sections -o test.elf

In the llvm case, there is a warning reported:
ld.lld: warning: test.c:(.test+0x4): has non-ABS relocation
R_ARM_THM_JUMP11 against symbol 'reset'
but it succeeds.

Finally, i check that the "start" symbol is placed at the correct address with:
llvm-objdump --syms test.elf
or
${CROSS_COMPILE}objdump --syms test.elf

The result is wrong for the llvm case (address is zero) and correct
for the gnu case (address is 0x1000).

Am i doing something wrong?
Is this difference between gnu and llvm expected or is it a bug?

LLVM/CLANG version: 13.0.0 (https://archlinux.org/)
GCC version: 11.2.1 (http://musl.cc/)
LD version: 2.37 (http://musl.cc/)

Regards,
  Vicenç.