From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-405016-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 2086 invoked by alias); 29 Oct 2012 14:43:00 -0000
Received: (qmail 32106 invoked by uid 48); 29 Oct 2012 14:42:10 -0000
From: "pierre.poissinger at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug preprocessor/55115] [>=4.5.0 regression] missing headers as fatal breaks cproto logic
Date: Mon, 29 Oct 2012 14:43:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: preprocessor
X-Bugzilla-Keywords:
X-Bugzilla-Severity: enhancement
X-Bugzilla-Who: pierre.poissinger at gmail dot com
X-Bugzilla-Status: WAITING
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Changed-Fields:
Message-ID: <bug-55115-4-R9gnioe90v@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-55115-4@http.gcc.gnu.org/bugzilla/>
References: <bug-55115-4@http.gcc.gnu.org/bugzilla/>
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
Content-Type: text/plain; charset="UTF-8"
MIME-Version: 1.0
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
X-SW-Source: 2012-10/txt/msg02692.txt.bz2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55115

--- Comment #3 from Pierre Poissinger <pierre.poissinger at gmail dot com> 2012-10-29 14:42:09 UTC ---
Hi,

Typically: The header is used, and contains all the 'visible' functions found
in source BUT it's only needed:
a) To perform real compilation: To check that function called are called
correctly
b) As export/header for the lib.

cproto only preproc the file via -E option.

Quick 'real life' example:
myfuncs.h: Auto generated proto, generated out of a.c and b.c
a.c: Define a(), calls b() - include 'myfuncs.h'
b.c: Define b() - include 'myfuncs.h'

=> the "include" of the generated myfuncs.h file is to avoid local definitions
+ allow early check if functions signature changes for whatever reasons.

Now - myfuncs.h being auto generated, during first build, prototyping will fail
quickly due to "Missing headers"... 
This create some kind of a "Chicken/Egg" problem :-)

If adding an option is annoying: Maybe then the 'fatal' should not be enforced
if run is limited to preproc only, aka '-E' ?