Problem with macros and templates

I'm trying to get two VS2008 projects (of which neither are written by me) that separately compiles just fine, to work together.

When I include a header from the first project in the second, I get this error:

Code:

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... Defs.hpp(195) : warning C4002: too many actual parameters for macro 'min'

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Here is the code that generates the error

Code:

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#define FW_CUDA_FUNC    __device__ __inline__

#define FW_SPECIALIZE_MINMAX(TEMPLATE, T, MINVAL, MAXVAL) \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b) { return MINVAL; } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b) { return MAXVAL; } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c) { return min(min(a, b), c); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c) { return max(max(a, b), c); } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c, T d) { return min(min(min(a, b), c), d); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c, T d) { return max(max(max(a, b), c), d); } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c, T d, T e) { return min(min(min(min(a, b), c), d), e); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c, T d, T e) { return max(max(max(max(a, b), c), d), e); } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c, T d, T e, T f) { return min(min(min(min(min(a, b), c), d), e), f); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c, T d, T e, T f) { return max(max(max(max(max(a, b), c), d), e), f); } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c, T d, T e, T f, T g) { return min(min(min(min(min(min(a, b), c), d), e), f), g); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c, T d, T e, T f, T g) { return max(max(max(max(max(max(a, b), c), d), e), f), g); } \
    TEMPLATE FW_CUDA_FUNC T min(T a, T b, T c, T d, T e, T f, T g, T h) { return min(min(min(min(min(min(min(a, b), c), d), e), f), g), h); } \
    TEMPLATE FW_CUDA_FUNC T max(T a, T b, T c, T d, T e, T f, T g, T h) { return max(max(max(max(max(max(max(a, b), c), d), e), f), g), h); } \
    TEMPLATE FW_CUDA_FUNC T clamp(T v, T lo, T hi) { return min(max(v, lo), hi); }


FW_SPECIALIZE_MINMAX(template <class T>, T&, (a < b) ? a : b, (a > b) ? a : b)

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Row 195 is the last row in the code above.

As both project compile separately, I'm thinking this has something to do with (pre?)compiler options. I've tried to isolate the error by looking at differences in settings between the two projects, but I don't really know where to look.

Any ideas would be greatly appreciated!

Make them template functions instead of macros.

Never create macros with lower-case names, especially for common names like min and max!
Template functions obey scope, at least, and don't give incomprehensible syntax errors everywhere.

Quote:

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Originally Posted by Elysia

Never create macros with lower-case names, especially for common names like min and max!
That said, the solution would be, like whiteflags said, to make them template functions. They obey scope, at least, and don't give incomprehensible syntax errors everywhere.

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That's overselling them. Template errors can be pretty bad too.

Yes, but they don't give syntax errors ;)

Template functions were my suggestion because that looks like what the poster wants to use. I don't need to sell my advice and I don't want anyone doing it for me.

Actually, looking at the OP with more scrutiny, the code is creating a bunch of template functions.

The problem seems to be that one project is creating min as a macro, and one as a template. This one is creating it as a template, so look at the other one. Probably, you will want to remove the macro.

Search for "#define min" and you may find it.

Quote:

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Originally Posted by Elysia

Never create macros with lower-case names, especially for common names like min and max!
That said, the solution would be, like whiteflags said, to make them template functions. They obey scope, at least, and don't give incomprehensible syntax errors everywhere.

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I think the macro generates templated min/max functions, so in the end there are no lowercase macros.

Anyway, I have a theory on where the problem might be.
PREVIOUSLY: I think the problem might be that one of the projects include <algorithm>, which defines templated min/max functions.
EDIT:When I look up min() or max() i VS, they are defined as macros in WinDef.h. The problem is that no file in the project seems to include WinDef.h, at least not directly. Can this be solved with namespaces somehow?

That's not what it looks like; I'd expect a different error message, if one at all. Creating a min function in the global namespace should not conflict with namespace std. Now it could be a non conforming standard library implementation.

As a quick fix, you could write #undef min above the code you posted. However, this may have other side effects.

Quote:

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Originally Posted by King Mir

That's not what it looks like; I'd expect a different error message, if one at all. Creating a min function in the global namespace should not conflict with namespace std. Now it could be a non conforming standard library implementation.

As a quick fix, you could write #undef min above the code you posted. However, this may have other side effects.

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Thanks! The #undef min and #undef max fixed it.

I admit I didn't read the original problem properly, but what you just saw is a prime example of why lower-case names for macros should not be used.
According to what I understand, you didn't do that, so that's good. But at least now you got to experience what devastation it can cause.

You could also define NOMINMAX before including windows.h, because that's always the problem when there's shenanigans with min or max identifiers.

Quote:

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Originally Posted by adeyblue

You could also define NOMINMAX before including windows.h, because that's always the problem when there's shenanigans with min or max identifiers.

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That sounds like a better solution, if that is indeed the source of the problem.

Quote:

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Originally Posted by adeyblue

You could also define NOMINMAX before including windows.h, because that's always the problem when there's shenanigans with min or max identifiers.

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Maybe they should rename that

#define NO_NONSENSE
or
#define GET_RID_OF_STUPIDITY

this problem could much more easily be solved by declaring the functions like so:

Code:

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template<typename T>
T getMin(std::initializer_list<T> theList);

template<typename T>
T getMax(std::initializer_list<T> theList);

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then you would call them like so:

Code:

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int theMax = getMax({1, 3, 5, 7, 9, 0});
double theMin = getMin({1.0, 3.0, 5.0, 7.0, 9.0, 0.0});

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