Re: preprocessor/1976

[neil at gcc dot gnu dot org]

The following reply was made to PR preprocessor/1976; it has been noted by GNATS.

From: neil@gcc.gnu.org
To: fl@abas.de, gcc-gnats@gcc.gnu.org, neil@gcc.gnu.org, nobody@gcc.gnu.org
Cc:  
Subject: Re: preprocessor/1976
Date: 14 Feb 2001 12:18:03 -0000

 Synopsis: different treatment of shift in preprocessor and compiler
 
 Responsible-Changed-From-To: unassigned->neil
 Responsible-Changed-By: neil
 Responsible-Changed-When: Wed Feb 14 04:18:02 2001
 Responsible-Changed-Why:
     Mine!
 State-Changed-From-To: open->closed
 State-Changed-By: neil
 State-Changed-When: Wed Feb 14 04:18:02 2001
 State-Changed-Why:
     This is not a bug.  In the preprocessor, all arithmetic
     is done in type int_max_t, which for you is a long long and
     64 bits; this cannot be changed.
     
     However, in the compiler expression, the type of "4" and "31" is "int", and so arithmetic is done in type int, i.e. 32 bits.  If you want the same answer, you need to use "4L".
     
     See sections 6.4.4.1, 6.5.7 and 6.10.1 of the standard.
 
 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view&pr=1976&database=gcc