gdb crashes after 'print *x' for fortran assumed size arrays

[Jeroen Makkinje]

In fortran one may use an asterisk if the size of
an array is unknown. However when evaluating the
array gdb crashes. To illustrate this I have made
the following program. The session below illustrate
what goes wrong.

I hope you can reproduce the error and fix the pro-
gram.

Greetings Jeroen Makkinje


(gdb) list test.f:1
1              PROGRAM TEST
2              Double Precision Av, X(10)
3              Integer I
4              Do 10 i = 1, 10
5              X(i) = 1.0D0 * i
6        10    Continue
7              Call CalcAv(Av, X,10)
8              print *, Av
9              End
10
(gdb) list
11             Subroutine CalcAv(Aver, xrange, j)
12             integer j
13             double precision Aver, xrange(*)
14             Aver = 0.0D0
15             Do 10 i = 1, j
16             Aver = Aver + xrange(i)
17        10   Continue
18             Aver = Aver / j
19             Return
20             End


(gdb) break 16
Breakpoint 1 at 0x8048f44: file test.f, line 16.


(gdb) run
Starting program: /home/jeroen/gdbtest/a.out
 
Breakpoint 1, calcav_ (aver=0xbffff858, xrange=0xbffff800, j=0x804f928)
    at test.f:16
16             Aver = Aver + xrange(i)
Current language:  auto; currently fortran


(gdb) print xrange
$1 = (PTR TO -> ( real*8 (-1))) 0xbffff800 

(gdb) print *xrange
Segmentation fault (core dumped) 

The problem is discovered when using ddd. When accidently moving
the mouse cursor over such so-called "assumed size array" the gdb
compiler crashes by ddd issues a output * command.

Greetings Jeroen Makkinje



+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

The program:
============



       PROGRAM TEST
       Double Precision Av, X(10)
       Integer I
       Do 10 i = 1, 10
       X(i) = 1.0D0 * i
 10    Continue
       Call CalcAv(Av, X,10)
       print *, Av
       End
 
       Subroutine CalcAv(Aver, xrange, j)
       integer j
       double precision Aver, xrange(*)
       Aver = 0.0D0
       Do 10 i = 1, j
       Aver = Aver + xrange(i)
  10   Continue
       Aver = Aver / j
       Return
       End
  


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g77 version 2.96 20000731 (Red Hat Linux 7.0) (from FSF-g77 version 0.5.26 
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Driving: g77 -v -c -xf77-version /dev/null -xnone
Reading specs from /usr/lib/gcc-lib/i386-redhat-linux/2.96/specs
gcc version 2.96 20000731 (Red Hat Linux 7.0)
 /usr/lib/gcc-lib/i386-redhat-linux/2.96/tradcpp0 -lang-fortran -v -D__GNUC__=2 
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-D__unix__ -D__linux__ -D__unix -D__linux -Asystem(posix) -Acpu(i386) 
-Amachine(i386) -Di386 -D__i386 -D__i386__ -D__tune_i386__ /dev/null /dev/null
GNU traditional CPP version 2.96 20000731 (Red Hat Linux 7.0)
 /usr/lib/gcc-lib/i386-redhat-linux/2.96/f771 -fnull-version -quiet -dumpbase 
g77-version.f -version -fversion -o /tmp/ccpfdudt.s /dev/null
GNU F77 version 2.96 20000731 (Red Hat Linux 7.0) (i386-redhat-linux) compiled
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GNU Fortran Front End version 0.5.26 20000731 (Red Hat Linux 7.0)
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GNU assembler version 2.10.90 (i386-redhat-linux) using BFD version 2.10.0.18
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@(#)LIBF77 VERSION 19991115
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@(#) LIBI77 VERSION pjw,dmg-mods 19991115
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