http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50455
--- Comment #1 from eda-qa at disemia dot com 2011-09-19 12:20:24 UTC --- The compiler/linker is silently ignoring that a class has been defined twice and this results in the linker linking to the incorrect constructor at instantiation time. This was found in a large set of libraries, but the two attached files reproduce the same problem. Reproduce: - Compile a program using the attached files and the instantiation in main() will use the wrong constructor. g++ -o test main.cpp duplicate.cpp Now, with optimizations the correct constructor is used, presumably since it is inlined and thus not subject to linking: g++ -O3 -o test main.cpp duplicate.cpp NOTE: The code is *invalid* but emits no diagnostic as one would expect. The issue is thus that the linker would be expected to emit a diagnostic message, likely an error about duplicate symbol.
