[Bug 480629] Re: [PR42535, fixed in 4.5] -fschedule-insns crashes g++

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** Changed in: gcc
   Importance: Unknown => Medium

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Title:
  [PR42535, fixed in 4.5] -fschedule-insns crashes g++

Status in The GNU Compiler Collection:
  Invalid
Status in “gcc-4.4” package in Ubuntu:
  Won't Fix

Bug description:
  Binary package hint: gcc-4.4

  g++ crashes when -fschedule-insns is activated, possibly because of
  other optimization options.

  brief foreword:

  if -O2 or -O3 is specified, while using boost::interprocess (1.40.0),
  pthread_mutex_unlock fails with EPERM in
  boost/.../interprocess_recursive_mutex.hpp:107 upon calling -- in my
  project -- managed_shared_memory::find. but everything's fine with -O1
  or the default -O0! extrapolating the offending code into a clean
  project, however, works seamlessly with both -O2 and -O3. NO crashes
  on g++ here, just a run-time assertion failure that I rooted to the
  EPERM failure.

  details:

  I thus tried to specify on my Makefile's CPPFLAGS the flag -O1 and I
  then added all the optimization switches triggered by -O2 and -O3, as
  specified by "man gcc". curiously enough, they crashed g++ on
  compiling the problematic module above (everything's ok with the other
  project's sources). checking by hand, I found out that simply removing
  -fschedule-insns both avoid the g++ crash AND solves my mutex problem.

  note that something like -O3 -fno-schedule-insns won't give any crash
  on g++ side, but will yield the described mutex problem.

  I'm a bit confused about these strange behaviors (why specifying the
  switches triggered by -O2 or -O3 is different than actually having -O2
  or -O3? why a run-time error depending on the optimization level, but
  not when the same code is compiled alone elsewhere?), but I hope they
  can be meaningful for improving gcc.

  (I believe the preprocessed input was sent attached this report,
  please let me know should this not be the case.)

  ProblemType: Crash
  Architecture: amd64
  Date: Wed Nov 11 11:47:42 2009
  DistroRelease: Ubuntu 9.10
  ExecutablePath: /usr/lib/gcc/x86_64-linux-gnu/4.4.1/cc1plus
  NonfreeKernelModules: wl nvidia
  Package: g++-4.4 4.4.1-4ubuntu8
  ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
  SourcePackage: gcc-4.4
  Uname: Linux 2.6.31-14-generic x86_64

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