[gfortran,patch] Add simplification for LBOUND/UBOUND without DIM argument

[FX Coudert <fxcoudert at gmail dot com>]

Hi all,

This fixes an ICE on valid code (PR 31591) due to UBOUND/LBOUND  
intrinsics not being simplified when there is not DIM argument  
provided, ie the result of UBOUND/LBOUND is an array. The following  
code is an example:

>   real :: x(5,5)
>   integer, parameter :: a(2) = ubound(x)
>   print *, a
>   end

This patch is simple. I move the one-dimensional simplification into  
a new function, simplify_bound_dim. This function is simply used for  
unidimensional simplication (when DIM is present). For  
multidimensional simplification, this function is used for each  
dimension of the array, and if all dimensions can be simplified, we  
create a constructor for the result. The only subtle issue revealed  
by testing is indicated by a comment:

+      if (upper && as->type == AS_ASSUMED_SIZE)
+       {
+         /* An error message will be emitted in
+            check_assumed_size_reference (resolve.c).  */
+         return &gfc_bad_expr;
+       }

This avoids emitting this error message twice. I tried hard but  
couldn't trigger a case where we would not go later into  
check_assumed_size_reference(), thus it's simpler that way.

Bootstrapped && regtested on i686-linux and x86_64-linux, OK for  
mainline?

FX


:ADDPATCH fortran:


2007-04-29  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

	PR fortran/31591
	* simplify.c (simplify_bound_dim): New function.
	(simplify_bound): Use the above. Perform simplification of LBOUND
	and UBOUND when DIM argument is not present.


2007-04-29  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

	PR fortran/31591
	* gfortran.dg/bound_simplification_1.f90: New test.

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