On Wed, Oct 27, 2010 at 12:23 AM, Ian Lance Taylor <iant@xxxxxxxxxx> wrote: > Jeffrey Walton <noloader@xxxxxxxxx> writes: > >> I've familiarized myself with ISO/IEC 14882 [1] and section 3.5 >> Program and Linkage. If a variable (g_Global above) satisfies >> paragraph/clause (9) (ie, names using external linkage in different >> scopes denotes the same object), where is it stated that constructors >> and destructors will run multiple times? I have not found anywhere in >> the standard where an object's constructor and destructors should be >> executed multiple times (cf, Section 12 Special member functions, >> Subsection 1, Constructors). > > The C++ standard doesn't cover shared libraries, so this is all outside > the scope of the standard. > > That said, I don't think that constructors should run multiple times in > this scenario, and I really can not explain what you are seeing. Can > you construct a small self-contained example with a series of commands > to run to show the problem? My simple test cases using Foo and Bar cannot duplicate. Using a live libcryptopp can cause a crash with dlopen and friends, but I have not been able to reduce it to something useful for a bug report. Possibly related: I did an audit of all SOs on a 'stock plus some' Ubuntu installation. 'plus some' includes the tool chain, emacs, OpenOffice and a few others. Nearly 300 of the 3500 crashed on a dlopen/dlclose cycle. I can't explain the [nearly] 10% failure rate, but I have not looked for the cause either. Jeff
