Re: libstdc++/47: Build of testsuite fails to compile bits/ios_base.h - exception not declared

[Benjamin Kosnik <bkoz at cygnus dot com>]

The following reply was made to PR libstdc++/47; it has been noted by GNATS.

From: Benjamin Kosnik <bkoz@cygnus.com>
To: anthony_w.geo@yahoo.com
Cc: libstdc++-gnats@sourceware.cygnus.com
Subject: Re: libstdc++/47: Build of testsuite fails to compile bits/ios_base.h - exception not declared
Date: Tue, 28 Mar 2000 15:38:17 -0800 (PST)

 this is from "mkcheck" including the new headers twice. Here's some mail 
 on the subject:
 
 http://sourceware.cygnus.com/ml/libstdc++/2000-q1/msg00452.html
 
 > I have tried building a new copy of gcc 2.95.2 with libstdc++ from the 2.90.8 snapshot, using gcc-2.95.2
 > 
 > It configures and builds OK, but when I run
 > 
 > make check
 > 
 > I get compilation erros on lots of the modules, huge reams of errors and warnings, starting with:
 > 
 > In file included from ../../../gcc-2.95.2/libstdc++/bits/std_ios.h:43,
 >                  from ../../../gcc-2.95.2/libstdc++/bits/std_istream.h:37,
 >                  from ../../../gcc-2.95.2/libstdc++/bits/std_fstream.h:37,
 >                  from ../../../gcc-2.95.2/libstdc++/std/fstream:2,
 >                  from ../../../gcc-2.95.2/libstdc++/testsuite/17_intro/header_fstream.cc:23:
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:144: parse error before `{'
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:152: destructor `failure' must match class name `ios_base'
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:226: parse error before `protected'
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:239: syntax error before `;'
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:243: parse error before `,'
 > ../../../gcc-2.95.2/libstdc++/bits/ios_base.h:245: missing ';' before right brace
 > 
 > I checked bits/ios_base.h, and it uses namespace std, whilst std_exception uses __STL_BEGIN_NAMESPACE
 > 
 > There are many headers that use each - shouldn't this be consistent across the source?
 > 
 > However, it appears the cause is the __GNUG__ macro - in std_exception.h we do #include<exception> if __GNUG__ is defined, otherwise we declare the exception class.
 > 
 > Fine, except that <exception> just does #include <bits/std_exception.h> - circular reference, and exception never gets declared.
 > 
 > It doesn't make any difference whether or not I specify --enable-namespaces or --disable-namespaces on the configure line
 > >How-To-Repeat:
 > Build + install binutils + gcc2.95.2 (normal) on sparc-solaris-2.7
 > 
 > rebuild gcc using libstdc++-2.90.8 as drop-in replacement for v2 libraries
 > 
 > make check
 > >Fix:
 > Remove the #ifdef __GNUG__ from bits/std_exception.h
 > ?
 > >Release-Note:
 > >Audit-Trail:
 > >Unformatted:
 >