[Bug c++/38172] warn_unused_result does not work with structs not containing a copy constructor

[joerg.richter@pdv-fs.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38172

Jörg Richter <joerg.richter@pdv-fs.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |joerg.richter@pdv-fs.de

--- Comment #5 from Jörg Richter <joerg.richter@pdv-fs.de> 2012-06-25 13:58:26 UTC ---
Adding just a simple struct member makes the warning for Bar2 disappear again.
Reopen? Or should I file a new PR?

$ cat t.cc
struct MyClass
{
    int i;
};

typedef struct MyClass MyClass;

int Bar1( void ) __attribute__((warn_unused_result));
MyClass Bar2( void ) __attribute__((warn_unused_result));

void Foo( void )
{
  Bar1(); // Warns
  Bar2(); // Does not warn
}

$ gcc -c -o /dev/null t.cc
t.cc: In function 'void Foo()':
t.cc:13:9: warning: ignoring return value of 'int Bar1()', declared with
attribute warn_unused_result [-Wunused-result]

$ gcc -v
Using built-in specs.
COLLECT_GCC=/tools/pkg/gcc/4.7.1/bin/gcc
COLLECT_LTO_WRAPPER=/tools/pkg/gcc/4.7.1/libexec/gcc/x86_64-unknown-linux-gnu/4.7.1/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: gcc-4.7.1/configure --enable-languages=c,c++
--disable-bootstrap --disable-nls --with-local-prefix=/not_existing_directory
--with-as=/tools/pkg/binutils/2.21/bin/as
--with-ld=/tools/pkg/binutils/2.21/bin/ld --prefix=/tools/pkg/gcc/4.7.1
Thread model: posix
gcc version 4.7.1 (GCC)

Also with 4.6.3