[tlbuild] hitex build failure

[Johannes Hielscher]

Confirmed (aarch64-linux). Martin did push an attempt to fix this
(TeXLive SVN -r62160), but the build failure persists.

The immediate reason for the broken compile (not its root cause) is the
changed default value of YYDEBUG from 0 to 1:
https://tug.org/svn/texlive/trunk/Build/source/texk/web2c/hitexdir/hiparser.h?r1=61723&r2=62150&pathrev=62160
Reverting this one-liner change makes the builds pass. But of course
there is an issue underneath -- changing debug settings shouldn't break
a build.

A peek into hishrink.c (created by ctangle from hiformat.w during the
build) shows that the CPP macro YYDEBUG is sourced from hiparser.h .
The variable "yydebug" is only ever declared, but defined nowhere.

When YYDEBUG==0, the preprocessor deletes this buggy code branch as a
whole.

A definition of "yydebug" happens in hiparser.c:1446, however, upon
superficial investigation, it seems that the preprocessor somehow
deletes this definition too: the variable "yydebug" does not appear in
the object file hishrink-hiparser.o (nm finds many "yy*" variables,
but "yydebug" is none of them), and the final linker call rightfully
complains about this.
I don't fully understand what happens there, and why. It seems to me
that the extent/scoping of the YYDEBUG preprocessor conditional within
hiparser.c might be off, or its logical state not propagated properly.

Best,
Johannes


Am Wed, 23 Feb 2022 22:31:07 +0000
schrieb Richard Koch <koch at uoregon.edu>:

> Same problem on macOS for arm:
> 
> Undefined symbols for architecture arm64:
>   "_yydebug", referenced from:
>       _main in hishrink-hishrink.o
> ld: symbol(s) not found for architecture arm64
> 
> Dick Koch