#1168 Swig doesn't know 'x' in macro

[Bugs Fly]

For a macro of the form:

#define CHR(ch1,ch2,ch3,ch4) (((ch1)<<24)|((ch2)<<16)|((ch3)<<8)|(ch4))
#define DEFAULT_LANG CHR('d','f','l','t')

swig generate:

SWIG_Python_SetConstant(d, "DEFAULT_LANG",SWIG_From_int((int)((((d) <<
24)|((f) << 16)|((l) << 8)|(t)))));

Which compiler will spit error as:

error: invalid operands to binary << (have ‘struct PyObject *’ and ‘int’)

error: ‘f’ undeclared (first use in this function)

note: each undeclared identifier is reported only once for each function it appears in

error: ‘l’ undeclared (first use in this function)

error: ‘t’ undeclared (first use in this function)

[Olly Betts]

This is probably connected to (and perhaps the same as):

https://sourceforge.net/tracker/?func=detail&aid=1474463&group_id=1645&atid=101645

[Olly Betts]

The other bug was fixed last year in 3.0.11, but this case still fails (though in a different way now):

  SWIG_Python_SetConstant(d, "DEFAULT_LANG",SWIG_From_int(static_cast< int >((( << 24)|( << 16)|( << 8)|))));

It looks like the issue is actually the parentheses around each character literal - if I remove those, then this works. Testing a fix.

A simpler testcase is:

%constant DEFAULT_LANG = ('d')<<24;

[Olly Betts]

Works in SWIG 4.0.2 so closing.