Bug#644975: clang looks at both versions 4.5 and 4.6 of libstdc++ headers

[Marc Glisse]

Package: clang
Version: 2.9-14
Severity: normal

Hello,

this is mostly a dup of 594820 (that I reported last year), but I was
asked to report it as a separate bug:

$ cat f.cc
#include <fenv.h>
$ clang++ -P -E f.cc
namespace std
{
  typedef long unsigned int size_t;
  typedef long int ptrdiff_t;
}
$

(compare with g++ which outputs the real content)

This happens because the include path contains /usr/include/c++/4.6
then /usr/include/c++/4.5 and later /usr/include, which breaks the
#include_next mechanism of fenv.h. clang needs to decide (either at
build-time or runtime) on one of 4.5 or 4.6 but it shouldn't have both.

ignoring nonexistent directory "/usr/include/c++/4.6//x86_64-linux-gnu/64"
ignoring nonexistent directory "/usr/bin/../lib/clang/2.9/include"
ignoring duplicate directory "/usr/include/c++/4.6"
ignoring duplicate directory "/usr/include/c++/4.6//backward"
ignoring duplicate directory "/usr/include/x86_64-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/4.6
 /usr/include/c++/4.6//backward
 /usr/include/c++/4.6//x86_64-linux-gnu
 /usr/include/c++/4.5
 /usr/include/c++/4.5/x86_64-linux-gnu
 /usr/include/c++/4.5/backward
 /usr/local/include
 /usr/include/x86_64-linux-gnu
 /usr/lib/gcc/x86_64-linux-gnu/4.6/include
 /usr/lib/gcc/x86_64-linux-gnu/4.6/include-fixed
 /usr/lib/gcc/x86_64-linux-gnu/4.5/include
 /usr/lib/gcc/x86_64-linux-gnu/4.5/include-fixed
 /usr/include

(it is a bit surprising that /usr/include/x86_64-linux-gnu ends up
before /usr/lib/gcc/x86_64-linux-gnu/*/*, but that shouldn't matter)

-- System Information:
Debian Release: wheezy/sid
  APT prefers testing
  APT policy: (500, 'testing'), (500, 'stable'), (50, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.0.0-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages clang depends on:
ii  libc6               2.13-21   
ii  libffi5             3.0.10-1  
ii  libgcc1             1:4.6.1-15
ii  libllvm2.9          2.9+dfsg-3
ii  libstdc++6          4.6.1-15  
ii  libstdc++6-4.6-dev  4.6.1-15  

Versions of packages clang recommends:
ii  llvm-2.9-dev  2.9+dfsg-3
ii  python        2.7.2-8   

clang suggests no packages.

-- no debconf information