[MacPorts] #36204: gcc47 empty string issue

[MacPorts]

#36204: gcc47 empty string issue
-------------------------+--------------------------------
 Reporter:  rob.patro@…  |      Owner:  macports-tickets@…
     Type:  defect       |     Status:  new
 Priority:  Normal       |  Milestone:
Component:  ports        |    Version:  2.1.2
 Keywords:               |       Port:
-------------------------+--------------------------------
 I'm trying to use the Boost iostream library in OSX with gcc 4.7 (since
 I'll be using C++11 features). The following code compiles and links, but
 fails at runtime:

 {{{
 #include <iostream>
 #include <fstream>
 #include <boost/iostreams/device/file.hpp>
 #include <boost/iostreams/filtering_stream.hpp>
 #include <boost/iostreams/filter/gzip.hpp>

 int main(int argc, char** argv) {

   std::string fname(argv[1]);

   std::ifstream file(fname.c_str(), std::ios_base::in |
 std::ios_base::binary);
   try {
     boost::iostreams::filtering_istream in;
     in.push(boost::iostreams::gzip_decompressor());
     in.push(boost::iostreams::file_source(fname));
     for( std::string str; std::getline(in, str); ) {
       std::cout << "Processed line " << str << '\n';
     }
    }
    catch(const boost::iostreams::gzip_error& e) {
    std::cout << e.what() << '\n';
   }
 }

 }}}

 With the following error:

 {{{
 test(70632) malloc: *** error for object 0x100168860: pointer being freed
 was not allocated
 *** set a breakpoint in malloc_error_break to debug
 }}}

 Running this under GDB, the stackframe is the following

 {{{
 Program received signal SIGABRT, Aborted.
 0x00007fff8b0d0d46 in __kill ()
 (gdb) bt
 #0  0x00007fff8b0d0d46 in __kill ()
 #1  0x00007fff88f52e1c in abort ()
 #2  0x00007fff88f26989 in free ()
 #3  0x00007fff84365e7c in std::string::reserve ()
 #4  0x00007fff8436606e in std::string::push_back ()
 #5  0x00007fff8436602d in std::string::operator+= ()
 #6  0x000000010006f307 in boost::iostreams::detail::gzip_header::process
 (this=0x113e8, c=6 '\006') at gzip.cpp:100
 #7  0x000000010000f435 in
 boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 >::read<boost::iostreams::detail::linked_streambuf<char,
 std::char_traits<char> > > ()
 #8  0x000000010000f13e in
 boost::iostreams::detail::read_filter_impl<boost::iostreams::multichar_tag>::read<boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 >, boost::iostreams::detail::linked_streambuf<char, std::char_traits<char>
 > > ()
 #9  0x000000010000edd7 in
 boost::iostreams::read<boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 >, boost::iostreams::detail::linked_streambuf<char, std::char_traits<char>
 > > ()
 #10 0x000000010000e557 in
 boost::iostreams::detail::flt_wrapper_impl<boost::iostreams::input>::read<boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 >, boost::iostreams::detail::linked_streambuf<char, std::char_traits<char>
 > > ()
 #11 0x000000010000e1d8 in
 boost::iostreams::detail::concept_adapter<boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 > >::read<boost::iostreams::detail::linked_streambuf<char,
 std::char_traits<char> > > ()
 #12 0x000000010000d020 in
 boost::iostreams::detail::indirect_streambuf<boost::iostreams::basic_gzip_decompressor<std::allocator<char>
 >, std::char_traits<char>, std::allocator<char>,
 boost::iostreams::input>::underflow ()
 #13 0x00000001000be63a in std::getline<char, std::char_traits<char>,
 std::allocator<char> > ()
 }}}

 I filed this under gcc instead of boost because it looks like the problem
 goes down to some
 very fundamental std::string code, and I assume boost isn't to blame here.
 It also leads me to
 believe this error might be encountered far outside this test case.

-- 
Ticket URL: <https://trac.macports.org/ticket/36204>
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