○ → powerpc64le-linux-gnu-gcc-10 -S app.d
app.d:1:8: error: module stdio is in file 'std/stdio.d' which cannot be read
    1 | import std.stdio;
      |        ^
import path[0] = /usr/lib/gcc-cross/powerpc64le-linux-gnu/10/include/d

This is a simple hello program that I wanted compile to POWER 8 or 9 from X86_64 host.

On Tuesday, 17 August 2021 at 18:18:35 UTC, Mahdi wrote:

○ → powerpc64le-linux-gnu-gcc-10 -S app.d
app.d:1:8: error: module stdio is in file 'std/stdio.d' which cannot be read
    1 | import std.stdio;
      |        ^
import path[0] = /usr/lib/gcc-cross/powerpc64le-linux-gnu/10/include/d

PPC doesn't have Phobos enabled by default, so I guess that the package maintainer for your distribution didn't bother including the sources either. Reason for not enabling Phobos is mostly down to lack of std.math support for the IBM real format.

Maybe there could be support for more granular turning on/off of individual Phobos packages. If that sounds something of interest, a bug report can be raised.