I'm trying to get code similar to this to compile: template<bool Flag> struct foo {static const bool bar = Flag;}; int main() { int a; int baz = foo<__builtin_constant_p(a)>::bar; } minimal.cpp: In function ‘int main()’: minimal.cpp:4:42: error: the value of ‘a’ is not usable in a constant…

Templates and __builtin-constant_p

nickgammon September 30, 2012, 11:03pm 5

I think you are misusing Flag in your first line. Can you explain what the intention is?

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