Re: g++ running async???

[Ángel González <keisial at gmail dot com>]

moze wrote:
> Hi,
>
> I have a weired phenomena, I want to discuss before filing a bug report.
> Sorry, source+data is too big for posting.
>
> I have a Programm(in C++) that calls "g++" to compile a number of cpp-files
> and afterwards calls "ar" to build a static lib.
> Both "g++" and "ar" are executed using posix_spawnp()+waitpid() (fork() has
> same behaviour)
>
> The Problem is that "ar" somtimes fails because the object-file I compiled
> just before doesn't exist!
>
> It seems like if waitpid() returnns before g++ is actually finished. A
> simple sleep of 0.5sec avoids the problem.
> The waitpid() seems to behave as expected:
> 1. wait longer for bigger cpp-files
> 2. wait-time matches output of -time
> 3. I get correct exit-code
> But the output-file appears later, and output of -time and -v also continue
> after waitpid() and even after my application has terminated...
>
> Am I missing something obvoius???
Maybe your g++ is spawning another process and returning without waiting 
it? Seems
an odd behavior (many makefiles would break, just as your program) but 
that's what the
behavior suggests.
I would strace your g++ looking for file and process creation.