[PATCH] Optimize 'a ' as single char string too

[Paul Richard Thomas]

Dear Tobias,

It was me that raised the question.

> b) For character comparison, TRIM does not play any role, cf.
>  "For a character relational intrinsic operation, the operands are
>  compared one character at a time in order, beginning with the first
>  character of each character operand. If the operands are of unequal
>  length, the shorter operand is treated as if it were extended on
>  the right with blanks to the length of the longer operand. If both
>  x1 and x2 are of zero length, x1 is equal to x2; if every character
>  of x1 is the same as the character in the corresponding position in
>  x2, x1 is equal to x2. Otherwise, at the first position where the
>  character operands differ, the character operand x1 is considered
>  to be less than x2 if the character value of x1 at this position
>  precedes the value of x2 in the collating sequence (1.3); x1 is
>  greater than x2 if the character value of x1 at this position
>  follows the value of x2 in the collating sequence."
>  (F2008, 7.1.5.5.1 Interpretation of relational intrinsic operations)

To which this is a satisfactory answer :-)

> Thus, the optimization of ignoring the tailing blanks for
>  if (c .eq. 'a ') call abort
> seems to be fine.

Indeed - thanks for digging into the standard.  I just wanted to be
sure that the trailing spaces had no lexographic value.

Cheers

Paul