-----Original Message----- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Vambola Kotkas
None of the available wave flags did seemingly help. Not that i need huge integers, however boost sometimes does have way bigger ones so it must be legal?
It's not. Or, more precisely, all values in expressions in #if or #elif directives are promoted to the largest built-in type--namely, long or unsigned long in current C++. Beyond that, if I recall correctly, underflow and overflow produced by arithmetic results in undefined behavior.
MS Visual C++ 7.1 processes constants like 18446744073709551615 without any noise. See ... 1.33.0 boost/cstdint.hpp line(263): # if ULONG_MAX == 18446744073709551615 // 2**64 - 1
Silly example 2: #define SHOW2(x) #x #define SHOW(x) SHOW2(Number is:##x) #pragma message( SHOW(__LINE__)) Result: test.cpp(3): error: pasting the following two tokens does not give a valid preprocessing token: ":" and "__LINE__" Maybe its buggy and MS made its preprocessor too lousy there ... just for reference Visual C++ 7.1 preprocess result:
It is undefined behavior to paste together two tokens where the result is not a single token. In this case, and in most cases like this, the concatenation is pointless: #define SHOW(x) SHOW2(Number is:x) Just for the record, BTW, VC++ has a horrible preprocessor. Regards, Paul Mensonides