Aro may erroneously emit tokens in diagnostics with 0 as their line number

[squeek502]

Previously, #604 and #608

A few places that use 0 as a line number have been introduced since:

arocc/src/aro/Preprocessor.zig

Line 1775 in 121472d

.line = 0,

arocc/src/aro/Preprocessor.zig

Line 1977 in 121472d

.loc = .{ .id = .generated, .byte_offset = 0, .line = 0 },

Are these intentional?

Relevant: https://codeberg.org/ziglang/zig/issues/35483

[Vexu]

Those tokens should not be used in diagnostics but they could be changed to something else to avoid any issues. It looks like the linked Zig issue hit #949.

[squeek502]

I guess what I'm really asking is should it be possible to safely do - 1 on line numbers or is that not meant to be guaranteed safe? See https://codeberg.org/ziglang/zig/pulls/35484

[Vexu]

It is meant to be safe.

[nektro]

$ curl -sL https://sqlite.org/2026/sqlite-autoconf-3530400.tar.gz | tar xzvf -

$ zig version
0.17.0-dev.2033+af24fd11a

$ zig translate-c sqlite-autoconf-3530400/sqlite3.c -lc
error: translation failure
<scratch space>:0:1: error: invalid token at start of a preprocessor expression

^

[squeek502]

Would be helpful if you could try reproducing with Aro directly. Likely has been fixed by #1011 but not downstreamed yet.