ruby segfaults

[Thomas Klausner <wiz%netbsd.org@localhost>]

Hi!

When using ruby 4.0.1 on NetBSD 11.99.5, I sometimes see
segfaults. The next try building the same program usually works.

My latest segfault was when building ocl-icd 2.3.3, here's the build
log:

===> Building for ocl-icd-2.3.3
/usr/pkg/bin/ruby40 icd_generator.rb --mode database --database ./ocl_interface.yaml \

/usr/pkg/bin/ruby40 icd_generator.rb --mode generate --database ./ocl_interface.yaml
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:312: [BUG] Segmentation fault at 0x00007f7fff1c7000
ruby 4.0.1 (2026-01-13 revision e04267a14b) +PRISM [x86_64-netbsd]

-- Control frame information -----------------------------------------------
c:0012 p:0003 s:0058 e:000057 l:n b:---- BLOCK  /usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:312 [FINISH]
c:0011 p:---- s:0050 e:000049 l:y b:---- CFUNC  :gsub
c:0010 p:0011 s:0045 e:000044 l:y b:0001 METHOD /usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:311
c:0009 p:0006 s:0038 e:000037 l:n b:---- BLOCK  /usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:329 [FINISH]
c:0008 p:---- s:0034 e:000033 l:y b:---- CFUNC  :each_value
c:0007 p:2379 s:0030 e:000029 l:y b:0001 CLASS  /usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:328
c:0006 p:0007 s:0027 e:000026 l:y b:0001 TOP    /usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:11 [FINISH]
c:0005 p:---- s:0024 e:000023 l:y b:---- CFUNC  :require
c:0004 p:0005 s:0019 e:000018 l:y b:0001 TOP    /usr/pkg/lib/ruby/4.0.0/rubygems.rb:9 [FINISH]
c:0003 p:---- s:0012 e:000011 l:y b:---- CFUNC  :require
c:0002 p:0012 s:0007 e:000006 l:y b:0001 TOP    <internal:gem_prelude>:2 [FINISH]
c:0001 p:0000 s:0003 E:001870 l:y b:---- DUMMY  [FINISH]

-- Ruby level backtrace information ----------------------------------------
<internal:gem_prelude>:2:in '<internal:gem_prelude>'
<internal:gem_prelude>:2:in 'require'
/usr/pkg/lib/ruby/4.0.0/rubygems.rb:9:in '<top (required)>'
/usr/pkg/lib/ruby/4.0.0/rubygems.rb:9:in 'require'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:11:in '<top (required)>'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:328:in '<module:RbConfig>'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:328:in 'each_value'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:329:in 'block in <module:RbConfig>'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:311:in 'expand'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:311:in 'gsub'
/usr/pkg/lib/ruby/4.0.0/x86_64-netbsd/rbconfig.rb:312:in 'block in expand'

-- Threading information ---------------------------------------------------
Total ractor count: 1
Ruby thread count for this ractor: 1

-- C level backtrace information -------------------------------------------
/usr/pkg/lib/libruby40.so.40(rb_profile_frame_full_label+0x246b) [0x75b39b34ecf4]
[0x75b39b157f6f]
[0x75b39b299346]
[0x75b39ad22040]
[0x75b39b16f437]
[0x75b39b170549]
[0x75b39b184037]
[0x75b39b184d07]
[0x75b39b185709]
[0x75b39b2ae337]
[0x75b39b2b2afd]
[0x75b39b2bec7c]
[0x75b39b33634b]
[0x75b39b337db8]
[0x75b39b33cdbe]
[0x75b39b2c5e5a]
[0x75b39b327dd1]
[0x75b39b32c8d4]
[0x75b39b332d30]
[0x75b39b337db8]
[0x75b39b33cdbe]
[0x75b39b189356]
[0x75b39b18ad32]
[0x75b39b2a4ab3]
[0x75b39b18bc8c]
[0x75b39b161725]
[0x75b39b18e33c]
[0x75b39b18f3f4]
[0x75b39b327dd1]
[0x75b39b32c8d4]
[0x75b39b332d30]
[0x75b39b337db8]
[0x75b39b1c4237]
[0x75b39b1c42df]
[0x75b39b1c4cc8]
[0x75b39b327dd1]
[0x75b39b33242d]
[0x75b39b337db8]
[0x75b39b1c4237]
[0x75b39b1c42df]
[0x75b39b1c4cc8]
[0x75b39b327dd1]
[0x75b39b33242d]
[0x75b39b337db8]
[0x75b39b289ffa]
[0x75b39b28bf78]
[0x75b39b28c420]
[0x75b39b162894]
[0x7dd5e3]

-- Other runtime information -----------------------------------------------

gmake: *** [Makefile:1667: stamp-generator] Segmentation fault (core dumped)
gmake: *** Waiting for unfinished jobs....
echo "timestamp" > stamp-generator-dummy
*** Error code 2

Any ideas?
 Thomas