Max common block size, global array size on ia32

Craig Tierney ctierney at
Tue Jul 23 16:43:12 PDT 2002

Sorry if this is a bit off topic.  I am not sure
where to ask this question.  The following
two codes fail on my system (Dual Xeon, 2 GB Ram,
Linux-2.4.18, redhat 7.2).

program memtest

integer*8 size
haracter a(size)   
common /block/ a

write(*,*) "hello"



char ar[896*1024*1024];

int main() { printf("Hello\n"); }

I get a segmentation fault before the codes
start.  I can use ifc, icc, pgf77 and gcc and
get the same results.   If I change the array size to 895 MB,
the codes run.  If I change the C code to
define the array as 'static char ar[blah]' I can
allocate more than 895MB.

I have bumped up the max stack size with:

ulimit -Hs 2048000
ulimit -s 2048000

But this does not help.

I cannot find anywhere in the linux source where
the max stacksize might be set.  It seems that
it might be tied to 1 GB, but I cannot find it.

Does anyone know how I can get around this


Craig Tierney (ctierney at

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