# Ruby & gprof and thread.so undefined reference to rb\_thread **URL:** \ **Category:** Ruby\ **Created:** [March 28, 2007, 4:39am UTC](https://www.ruby-forum.com/t/ruby-gprof-and-thread-so-undefined-reference-to-rb-thread/90364 "2007-03-28T04:39:48Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![amin1426](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/4da419/32.png) [@amin1426](https://www.ruby-forum.com/u/amin1426)\ **Post date:** [March 28, 2007, 4:39am UTC](https://www.ruby-forum.com/t/ruby-gprof-and-thread-so-undefined-reference-to-rb-thread/90364/1 "2007-03-28T04:39:48Z")
So I was sitting there glaring at the screen whilst my script went off and did lots and lots… …and started to think wonder how I could make it a little faster… After all, I have thrown every trick in the [http://www.rubygarden.org:3000/Ruby/page/show/RubyOptimization](http://www.rubygarden.org:3000/Ruby/page/show/RubyOptimization) book at the Ruby level (indeed I wrote a most of that) Now I started to wonder if I could tweak Ruby itself to run a little faster… So profile first… CFLAGS=‘-p -pg -O2’ LDFLAGS=‘-p -pg’ ./configure –program-suffix=-profile make CFLAGS=‘-p -pg -O2’ LDFLAGS=‘-p -pg’ su make install CFLAGS=‘-p -pg -O2’ LDFLAGS=‘-p -pg’ It seems to work and run for the basic stuff, lets hit the Big Script… Oh dear! undefined reference to rb\_thread\_critical in thread.so Oh, dear. Here’s the shortest bit that triggers it… irb-profile -rthread /usr/local/lib/ruby/1.8/i686-linux/thread.so: /usr/local/lib/ruby/1.8/i686-linux/thread.so: undefined symbol: rb\_thread\_critical - /usr/local/lib/ruby/1.8/i686-linux/thread.so (LoadError) from /usr/local/lib/ruby/1.8/thread.rb:5 from /usr/local/lib/ruby/1.8/irb/init.rb:252:in `require' from /usr/local/lib/ruby/1.8/irb/init.rb:252:in `load\_modules’ from /usr/local/lib/ruby/1.8/irb/init.rb:250:in `each' from /usr/local/lib/ruby/1.8/irb/init.rb:250:in `load\_modules’ from /usr/local/lib/ruby/1.8/irb/init.rb:21:in `setup' from /usr/local/lib/ruby/1.8/irb.rb:54:in `start’ from /usr/local/bin/irb-profile:13 Anyone with any guesses what to do? John C. Phone : (64)(3) 358 6639 Tait Electronics Fax : (64)(3) 359 4632 PO Box 1645 Christchurch Email : removed\_email\_address@domain.invalid New Zealand ---
**Author:** ![amin1426](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/4da419/32.png) [@amin1426](https://www.ruby-forum.com/u/amin1426)\ **Post date:** [March 28, 2007, 5:09am UTC](https://www.ruby-forum.com/t/ruby-gprof-and-thread-so-undefined-reference-to-rb-thread/90364/2 "2007-03-28T05:09:53Z")
John C. wrote: > Oh dear! > (LoadError) > /usr/local/lib/ruby/1.8/irb/init.rb:21:in `setup’ > New Zealand 1. Recompile without the -O2 and see if it goes away. “Normally”, when one compiles for profiling, one uses “-g -pg” which forces _no_ optimization. 2. If the recompiled (and stock Ruby) work, it’s a GCC problem. If the recompiled doesn’t work and the stock Ruby does, check your configuration parameters on your profiling build. Incidentally, I’ve done a few tests with a profiling Ruby and I’ve never hit anything like this, but nothing I’ve done goes anywhere near threading. By the way, what version of GCC are you using? And are you building the non-profiling Ruby from source too? – M. Edward (Ed) Borasky, FBG, AB, PTA, PGS, MS, MNLP, NST, ACMC(P) [http://borasky-research.blogspot.com/](http://borasky-research.blogspot.com/) If God had meant for carrots to be eaten cooked, He would have given rabbits fire. ---
**Author:** ![amin1426](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/4da419/32.png) [@amin1426](https://www.ruby-forum.com/u/amin1426)\ **Post date:** [March 28, 2007, 5:38am UTC](https://www.ruby-forum.com/t/ruby-gprof-and-thread-so-undefined-reference-to-rb-thread/90364/3 "2007-03-28T05:38:54Z")
Thanks for your suggestions, alas, it didn’t resolve the issue. On Wed, 28 Mar 2007, M. Edward (Ed) Borasky wrote: > 1. Recompile without the -O2 and see if it goes away. Alas not. > 1. If the recompiled (and stock Ruby) work, it’s a GCC problem. If the > recompiled doesn’t work and the stock Ruby does, check your configuration > parameters on your profiling build. Compiling without -pg works fine. Compiling with -pg and –disable-shared fails. > By the way, what version of GCC are you using? > gcc-4.1.2 ubuntu edgy eft > And are you building the non-profiling Ruby from source too? > Yip, works fine. > If God had meant for carrots to be eaten cooked, He would have given rabbits > fire. He gave us fire so we can eat carrots in the form of cooked rabbits? Thanks! John C. Phone : (64)(3) 358 6639 Tait Electronics Fax : (64)(3) 359 4632 PO Box 1645 Christchurch Email : removed\_email\_address@domain.invalid New Zealand ---
**Author:** ![amin1426](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/4da419/32.png) [@amin1426](https://www.ruby-forum.com/u/amin1426)\ **Post date:** [March 28, 2007, 6:35am UTC](https://www.ruby-forum.com/t/ruby-gprof-and-thread-so-undefined-reference-to-rb-thread/90364/4 "2007-03-28T06:35:59Z")
John C. wrote: > > configuration parameters on your profiling build. > > Compiling without -pg works fine. Compiling with -pg and > –disable-shared fails. > I’m not familiar with “disable-shared”, but I suspect it builds static > libraries instead of shared ones. I think you _want_ shared libraries. > But if “-pg” is the problem, it’s probably GCC. I’ve got 4.1.2 on my > (Gentoo) systems and I’ve never seen a problem like this with “-pg”. The > only issue I’ve had at all is that both Ruby and Tcl/Tk have to be built > either with threads or without threads – you can’t mix them. This works on my box: # build profiling Ruby mkdir profiling-ruby-build cd profiling-ruby-build CFLAGS=‘-g -pg’ …/ruby/configure --disable-install-doc --enable-pthread –prefix=/home/test/profiling-ruby make; make install > He gave us fire so we can eat carrots in the form of cooked rabbits? > > Thanks! > > John C. Phone : (64)(3) 358 6639 > Tait Electronics Fax : (64)(3) 359 4632 > PO Box 1645 Christchurch Email : removed\_email\_address@domain.invalid > New Zealand – M. Edward (Ed) Borasky, FBG, AB, PTA, PGS, MS, MNLP, NST, ACMC(P) [http://borasky-research.blogspot.com/](http://borasky-research.blogspot.com/) If God had meant for carrots to be eaten cooked, He would have given rabbits fire.