From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Buck <jbuck@racerx.synopsys.com>
To: richbaum@acm.org
Cc: gcc@gcc.gnu.org
Subject: Re: Trigraph warnings when compiling linux-2.4.0-prerelease1
Date: Mon, 01 Jan 2001 15:16:00 -0000
Message-id: <200101012315.PAA08380@racerx.synopsys.com>
References: <3A507E7C.4279.3313E2@localhost>
X-SW-Source: 2001-01/msg00014.html

> I get the following warnings when compiling the latest linux kernel 
> with the 20001225 gcc snapshot:
...
> devlist.h:1278:33: warning: trigraph ??) ignored
...
> The lines are as follows:
> devlist.h:
> line 1278: 	DEVICE(109e,036c,"Bt879(??) Video Capture")
> line 6370:   VENDOR(2a15,"3D Vision(???)")
> 
> imm.c:
> line 929: 	printk("imm: parity error (???)\n");
> line 938: 	printk("imm: bad interrupt (???)\n");

This is a kernel bug.  That is, a strict ISO C compiler
must print

imm: bad interrupt (?]

for the last line, since ??) is the trigraph for ].  Many C compilers
other than gcc will just print that and never tell you there's a problem.

By default, gcc disables trigraphs, but if you give the -ansi flag
they are enabled.  But it warns about inputs that give different behavior
with and without trigraphs.

> them?  I felt this would be the appropriate list to send this to since 
> it compiles without these warnings with egcs-1.1.2.

You just found a bug in egcs-1.1.2 then.

The kernel should be changed, to, for example

> line 938: 	printk("imm: bad interrupt (??\?)\n");

Please direct complaints to the ANSI C committee for inflicting this
trigraphs botch on us all.