Recently found out LDC supports cross-compiling to riscv, but while trying it out I can't seem to make it work. I am very likely missing something simple, as I haven't done something like this before. I've already been told it's likely something with linking, though I'm not sure how to set this up. (Nor even without imports & confined to 1 file)

Using a simple single '.d' file with no imports: Error: cannot find program 'cc'
With imports it's a longer issue:

E:\Code\D\Overig>ldc2 --mtriple=riscv32 --mcpu=generic-rv32 -c source/app.d
C:\Program Files\LDC 1.32\bin\..\import\std\stdio.d(49): Error: module `core.stdc.stddef` import `wchar_t` not found
C:\Program Files\LDC 1.32\bin\..\import\core\stdc\time.d(34): Error: undefined identifier `time_t`, did you mean function `time`?
... (many similar errors here)
C:\Program Files\LDC 1.32\bin\..\import\core\stdc\wchar_.d(175): Error: undefined identifier `wchar_t`, did you mean `dchar`?

Note, the command I'm using is: ldc2 --mtriple=riscv32 --mcpu=generic-rv32 -c source/app.d

I've also wanted to look into dub's --arch=riscv32 command, which should function given what I've read, though this just states it's not supported. (Even though I believe it should be using ldc for this?)

Apologies for naïvity here, I cant really find any examples or guidance.

On Wednesday, 5 July 2023 at 17:00:53 UTC, HuskyNator wrote:

I haven't tried to compile to RiscV32, nor do know how it works. But this reads like LDC is not finding the C compiler it's trying to use.

LDC uses a C compiler to call the linker, instead to calling the linker directly.

You try to use C declarations, but they are specific to each C library, and different C libraries have different declarations, so headers can't decide which C library declarations to use. Try -mtriple=riscv32-unknown-linux

Worked for me on ldc 1.20 https://forum.dlang.org/post/vuxuftogvszztdrrtbne@forum.dlang.org

On Monday, 10 July 2023 at 14:09:47 UTC, Kagamin wrote:

It seems to be somewhat transformative, this at least gets me different errors :).
Where does this -unknown-linux postfix come from? ldc2 -version/-help did not mention it.

C:\Program Files\LDC 1.32\bin\..\import\core\stdc\stdio.d(1308): Error: function `core.stdc.stdio.vfprintf` `pragma(printf)` functions must be `extern(C) int vfprintf([parameters...], const(char)*, va_list)`
C:\Program Files\LDC 1.32\bin\..\import\core\stdc\stdio.d(1311): Error: function `core.stdc.stdio.__isoc99_vfscanf` `pragma(scanf)` functions must be `extern(C) int __isoc99_vfscanf([parameters...], const(char)*, va_list)`

et cetera

For reference, this code is purely:

module overig.app;
import std.stdio: writeln, readln;

int foo(int a, int b){
	return a+b;
}

void main() {
	int a = foo(1,2);
	writeln(a);
}

Probably bug in druntime, v-functions shouldn't have pragma(printf), because they don't have arguments to check.

Maybe the problem is with va_list, try to compile with -mtriple=riscv64-unknown-linux -mcpu=generic-rv64