Re: c++/7327: -isystem and template linkage

[Ben Hines <bhines@alumni.ucsd.edu>]

The following reply was made to PR c++/7327; it has been noted by GNATS.

From: Ben Hines <bhines@alumni.ucsd.edu>
To: gcc-gnats@gcc.gnu.org,
 gcc-prs@gcc.gnu.org,
 hoel@germanlloyd.org,
 gcc-bugs@gcc.gnu.org,
 jason@gcc.gnu.org
Cc:  
Subject: Re: c++/7327: -isystem and template linkage
Date: Sun, 3 Nov 2002 20:21:19 -0800

 This bug# 7327 also affects Apple's GCC on Mac OS X. Also, "idirafter" 
 is also affected in addition to "isystem".
 
 To reproduce on mac os x:
 
 in conftest.cpp:
 
 #include <conftest.h>
 int main ()
 {
    return 0;
 }
 
 in conftest.h in pwd:
 #include <iosfwd>
 
 Compile with:
 
 g++ -idirafter `pwd` conftest.cpp -save-temps
 OR
 g++ -isystem `pwd` conftest.cpp -save-temps
 
 RESULT:
   % g++ -idirafter `pwd` conftest.cpp -save-temps
 In file included from /usr/include/gcc/darwin/3.1/g++-v3/iosfwd:45,
                   from /Users/ben/tempbug/conftest.h:1,
                   from conftest.cpp:2:
 /usr/include/gcc/darwin/3.1/g++-v3/bits/stringfwd.h:49: template with C 
 linkage
 /usr/include/gcc/darwin/3.1/g++-v3/bits/stringfwd.h:57: template with C 
 linkage
 /usr/include/gcc/darwin/3.1/g++-v3/bits/stringfwd.h:61: template with C 
 linkage
 -snip more-
 
 REGRESSION:
 If i include <iosfwd> directly in conftest.cpp, i don't get the 
 problem. It has to be in a header found by isystem.
 
 % gcc -v
 Reading specs from /usr/libexec/gcc/darwin/ppc/3.1/specs
 Thread model: posix
 Apple Computer, Inc. GCC version 1161, based on gcc version 3.1 
 20020420 (prerelease)
 
 % uname -a
 Darwin lsanca1-ar8-4-60-073-020.lsanca1.dsl-verizon.net 6.1 Darwin 
 Kernel Version 6.1: Fri Sep  6 23:24:34 PDT 2002;
 root:xnu/xnu-344.2.obj~2/RELEASE_PPC  Power Macintosh powerpc
 
 -Ben