Re: gcc 16 bootstrap, stage 2 and 3 differ

On Thu, 13 Aug 2026, Thomas Klausner wrote:

> I have a problem when packaging gcc 16.1.0 for pkgsrc.  Using the same
> flags and patches that work for gcc 15.3.0, I see a problem late in
> the build when the stage2 and stage3 files are compared:
>
> Comparing stages 2 and 3
> warning: gcc/cobol/parse.o differs
> Bootstrap comparison failure!
> gcc/build/genoutput.o differs
> gcc/build/gensupport.o differs
> gcc/build/genrecog.o differs
> gcc/build/genmatch.o differs
> ... and many more ...
>

No real insight here except to ask, are the same command lines being passed
to both the stage2 and stage3 compilers?

Also,

> Contents of the .debug_loclists section:
>
> Table at Offset 0
> -  Length:          0x2665e
> +  Length:          0x2667b
>   DWARF version:   5
>

NetBSD's system compiler defaults to DWARF 4 because the CTF tools don't
support DWARF 5--everyting else, binutils, gdb, etc. work fine with DWARF 5.

> For now, the package (lang/gcc16) is using the --disable-bootstrap
> workaround.
>

You could compare only the code bits (ie. omit the debug section comparisons
which're added by as(1)from binutils  anyway). The build instructions suggest
Β‘bootstrap-debugΒ’:

https://gcc.gnu.org/install/build.html

-RVP