toolchain/59704: spurious build failure

[martin%NetBSD.org@localhost]

>Number:         59704
>Category:       toolchain
>Synopsis:       spurious build failure
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    toolchain-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Oct 11 14:35:00 +0000 2025
>Originator:     Martin Husemann
>Release:        NetBSD 11.99.3
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD martins.aprisoft.de 11.99.3 NetBSD 11.99.3 (GENERIC) #288: Sat Oct 11 08:22:30 CEST 2025 martin%martins.aprisoft.de@localhost:/home/martin/current/src/sys/arch/amd64/compile/GENERIC amd64
Architecture: x86_64
Machine: amd64
>Description:

This happend on the auto build cluster (but only once so far):

ln: unwind.h: File exists
--- unwind.h ---

*** Failed target: unwind.h
*** In directory: /home/source/ab/HEAD/src/external/gpl3/gcc/lib/libgcc/libgcov
*** Failed commands:
        ${_MKMSG} "symlink " ${.CURDIR:T}/${.TARGET}
        => @# "symlink " libgcov/unwind.h
        rm -f ${.TARGET}
        => rm -f unwind.h
        ln -s ${.ALLSRC} ${.TARGET}
        => ln -s /home/source/ab/HEAD/src/external/gpl3/gcc/dist/libgcc/unwind-generic.h unwind.h
*** [unwind.h] Error code 1

nbmake[6]: stopped making "includes" in /home/source/ab/HEAD/src/external/gpl3/gcc/lib/libgcc/libgcov
nbmake[6]: 1 error

nbmake[6]: stopped making "includes" in /home/source/ab/HEAD/src/external/gpl3/gcc/lib/libgcc/libgcov


build.sh command line was:

/home/source/ab/HEAD/src/build.sh -m amd64 -B 20251011125806Z -V NETBSD_OFFICIAL_RELEASE=no -D /home/builds/ab/HEAD/amd64/20251011125806Z-dest -M /home/builds/ab/HEAD/amd64/20251011125806Z-obj -R /home/builds/ab/HEAD/amd64/20251011125806Z-rlse -T /home/builds/ab/HEAD/amd64/20251011125806Z-tools -U -X /home/source/ab/HEAD/xsrc -P -x -N0 -V TMPDIR=/tmp -V BUILD=yes -V MAKECONF=/dev/null -V MKDEBUG=yes -j4 -VBUILDINFO=src@cvs:HEAD:20251011125806-xsrc@cvs:HEAD:20250920171020 -VMKREPRO_TIMESTAMP=1760187486 release iso-image install-image live-image


>How-To-Repeat:
s/a

>Fix:
8~n/a