http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50937
--- Comment #7 from Steve Kargl <sgk at troutmask dot apl.washington.edu> 2011-10-31 19:50:41 UTC --- On Mon, Oct 31, 2011 at 07:25:38PM +0000, fwi at inducks dot org wrote: > > Has the bug been corrected in recent versions of gfortran, or do you really > mean it's OK that gfortran claims an array has been allocated when it really > has not been? > Yes, the problem of integer overflow that Janne mentioned has been corrected. As to gfortran claiming "that an array has been allocated when it really has not been", suggests that you may not understand how your operating system works. The concise story is that gfortran asks your OS for a gazillion bytes of memory and please confirm the status. The OS tells gfortran (actually your compiled code), here's your gazillion bytes of virtual memory and everything is a-okay. As long as you do not actually touch the pages of allocated virtual memory, no physical memory has been allocated to your program. Once you start touching pages, at some point the OS notices a shortage of physical memory. This shortage leads to swapping other (idle) processes out to secondary storage, utilizing swap space as the backing storage for your virtual memory, evidently your process exceeds its limits or the system limits and the process segfaults.
