Two bugs (2.0.16 on Linux/Alpha)

["Matias Atria (F. de Ciencias Depto Matematicas)" <matria@abello.dic.uchile.cl>]

My apologies if someone reported this before (especially the first problem
below), but I have not followed this list with much attention in the last
weeks.

I'm running...
                    GP/PARI CALCULATOR Version 2.0.16 (beta)
                       Alpha running linux 64-bit version
                (readline v2.2 enabled, extended help available)

...and found two bugs.

? matrix(1000,5000,i,j,cos(0.5*i*j))
  ***   user interrupt after 1031099962854h, 339 ms.
                             ^^^^^^^^^^^^^^^^^^^^^^
(I obviously did not wait 1e9 years to interrupt it) The same thing happens
whenever I use the timer.

? allocatemem(256000000)
? matrix(1000,5000,i,j,cos(0.5*i*j))
  ***   the PARI stack overflows !!!

  ***   Warning: doubling stack size; new stack = 512000000.

I repeated this with a stack of 800Mb and it gave me the same problem. I
cannot imagine how PARI could need such a big amount of memory for such a
simple calculation. Is it a GC problem?

Thanks,
Matias.