[m-rev.] for review: write direct to .err files

[Zoltan Somogyi]

On 2023-09-15 17:16 +10:00 AEST, "Peter Wang" <novalazy at gmail.com> wrote:
> There's no reason to open the error stream for a target until its
> dependencies have successfully been made, and it doesn't.
> 
> make_module_target
>  1. calls make_dependency_files first
>     (and make_dependency_files calls make_module_target recursively),
>  2. before calling build_target, which opens/closes the error stream.
>     build_target doesn't make dependencies.

That does make sense. However, it also makes me wonder about
*why* the original author of the code that this diff modifies
wrote it to write the compiler's output to a temporary file and
then copy it to the .err file, instead of writing it to the .err file
directly.

Zoltan.