preprocessor/4923: Concatenation appears to handle whitespace incorrectly

[s0009525@chelt.ac.uk]

>Number:         4923
>Category:       preprocessor
>Synopsis:       Concatenation appears to handle whitespace incorrectly
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Nov 21 08:36:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     s0009525@chelt.ac.uk
>Release:        gcc version 2.95.2 20000220
>Organization:
>Environment:
(Debian) Linux 2.4.12-shells1 i686
>Description:
With the ## operator, if one of the arguments is a macro function, the whitespace around the arguments is not eaten, which is contrary to the GNU cpp documentation.
>How-To-Repeat:
/* test.h */

#define FOO(x) x
#define BAR    FOO(abc) ## def
BAR

/* cpp < test.h */

# 1 ""
 abc  def
>Fix:
None Found.
>Release-Note:
>Audit-Trail:
>Unformatted: