Bug 80177

Description of problem:
compiling such test case:
test.cc:
struct  QCString
{
    QCString( int size ) {};
    QCString( const char *str ) {};
};

inline bool operator==( const QCString &s1, const QCString &s2 )
{ return 0; }

enum EStyle
{
    FS_SOLID
};

static EStyle   getFillStyle() { return FS_SOLID; }

int main()
{
    if(getFillStyle() == "FS_SOLID") {}; // error here, FS_SOLID, 
not "FS_SOLID" must be
}

with command line: `g++ test.c`
GNU C++ compiler accepts the test case without any warnings!
Comparing 'enum EStyle' and 'char *' it IMPLICITLY casts enum to int, then int 
to QCString, from other side IMPLICITLY casts 'char *' to QCString and finally 
compares these using inline bool operator==( const QCString &s1, const 
QCString &s2 ) operator. That's incredible! Too much flexibility is used here; 
therefore erroneous code passed "strict" C++ checking. As a result hard-to-find 
run-time error will be.

This test case was distilled from koffice application from Red Hat 8.0 Linux 
distribution.
C++ compiler should do stricter checking. In this test case it should emit 
error about incomparable types.


Version-Release number of selected component (if applicable):


How reproducible:
always

Steps to Reproduce:
1. g++ test.cc (test.cc is in description)

    
Actual results:
Succesfully compiled ill-formed code.

Expected results:
Compilation error.

Additional info: