[patch] Fix fortran/25031, multiple allocations

[Brooks Moses]

Steve Kargl wrote:
> On Wed, Mar 01, 2006 at 06:03:26PM -0800, Brooks Moses wrote:
>>F95 Draft Standard, 6.3.1.1: "An allocatable array that has been 
>>allocated by an ALLOCATE statement and has not been subsequently 
>>deallocated (6.3.3) is *currently allocated* and is definable. 
>>Allocating a currently allocated allocatable array causes an error 
>>condition in the ALLOCATE statement."  (emphasis in original)
> 
> So?  An "error condition" does not mean that the program fails.
> It means that if one had used STAT=, then one can determine if
> an "error condition" occurred.  AFAICT, the Standard does not
> prohibit a memory leak.  NAG's compiler compiles the above and
> Lahey's web based checker also compiles the code.

Point taken; I should have thought more about what "error condition" 
means in standard-speak, rather than assuming.

However, in 6.3.1 just above the 6.3.1.1 section heading is the comment: 
"If an error condition occurs during execution of an ALLOCATE statement 
that does not contain the STAT= specifier, execution of the program is 
terminated."

The preceeding paragraph seems to me to say that, when STAT= is present, 
it should indicate the error condition, and that the allocated array in 
your example should be either allocated as x(4) or x(3), though which of 
those it ends up as is processor-dependent.  I believe it's a 
quality-of-implementation issue that the compiler should avoid creating 
memory leaks in such a case.

- Brooks