On 2023-12-11 10:07 AM, Christoph Hellwig wrote:
>> +CFLAGS_REMOVE_neon1.o += $(CC_FLAGS_NO_FPU)
>> +CFLAGS_REMOVE_neon2.o += $(CC_FLAGS_NO_FPU)
>> +CFLAGS_REMOVE_neon4.o += $(CC_FLAGS_NO_FPU)
>> +CFLAGS_REMOVE_neon8.o += $(CC_FLAGS_NO_FPU)
>
> Btw, do we even really need the extra variables for compiler flags
> to remove? Don't gcc/clang options work so that if you add a
> no-prefixed version of the option later it transparently gets removed?
Unfortunately, not all of the relevant options can be no-prefixed:
$ cat float.c
int main(void) { volatile float f = 123.456; return f / 10; }
$ aarch64-linux-musl-gcc float.c
$ aarch64-linux-musl-gcc -mgeneral-regs-only float.c
float.c: In function 'main':
float.c:1:33: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
1 | int main(void) { volatile float f = 123.456; return f / 10; }
| ^
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
1 | int main(void) { volatile float f = 123.456; return f / 10; }
| ~~^~~~
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types
$ aarch64-linux-musl-gcc -mgeneral-regs-only -mno-general-regs-only float.c
aarch64-linux-musl-gcc: error: unrecognized command-line option '-mno-general-regs-only'; did you mean '-mgeneral-regs-only'?
$
