http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51283
Bug #: 51283 Summary: g++ yields different behaviour for postfix increment and decrement operators with fundamental types vs. classes Classification: Unclassified Product: gcc Version: 4.6.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassig...@gcc.gnu.org ReportedBy: dicom...@gmail.com dico:~$ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6.1/lto-wrapper Target: i686-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.6.1-9ubuntu3' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-objc-gc --enable-targets=all --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu Thread model: posix gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3) dico:~$ cat ./main.cpp #include <vector> #include <assert.h> using namespace std; int main () { int i = 0; assert(i++ == i++); // OK int* p = 0; assert(p++ == p++); // OK vector<int> v(10, 10); vector<int>::iterator it = v.begin(); assert(it++ == it++); // FAILS return 0; } dico:~$ g++ ./main.cpp && ./a.out a.out: ./main.cpp:15: int main(): Assertion `it++ == it++' failed. Aborted GCC should calculate expression (it++ == it++) with an object copy returned by the overload it.operator ++ (int) method like for the first two examples.