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VLA parameters not accepted by g++?

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Reading the gcc 5.1 manual it seems that VLA parameters must be accepted by g++. For example the following is fine when compiled with gcc --std=gnu11

float sum (int M, float x[M]) {
 return x[0] + x[1];
}

int main (void) {
 float xs[2] = {1, 2};
 float acc = sum (2, xs);
 return 0;
}

But it is rejected by g++ --std=gnu++11. Is this possible at all with g++?

posted Jun 28, 2015 by Alok Sharma

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1 Answer

0 votes

No, I don't think so, G++ only supports some kinds of VLA.

You have to use float x[] or float* x in C++.

answer Jun 28, 2015 by Sanketi Garg
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The error with g++ is :

test.cpp: In static member function "static void B::SomeMethod()":
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Is there is a option to indicate to g++ to evaluate the template functions only when a specialization is called, and not before ?

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I'm not a c++/template guru and i can't decide if this is really a valid code or i have encountered a gcc bug:

template  struct A {
 void *p;
};
template  struct B : A {
 void *foo() { return p; }
};

g++ says "error: 'p' was not declared in this scope". microsoft's compiler is happy with the same code.

Can anyone help?

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