Constant array size

alman9898 · 04-23-2008, 02:17 PM

I know in C, arrays have to of a constant size.

However when I do something like:

const int size = 10;
int list[size];

I get thrown an error that the array size must be a constant expression (at the line where the array is declared). However, when in C++ when I do this it compiles fine. I'm using Visual Studio 2005, by the way.

However, when I switch to "Compile as C++ code" it compiles the .c file correctly. So is this valid for any C code, or just the Visual Studio compiler?

ShosMeister · 04-25-2008, 12:29 PM

Alman, welcome!! I haven't looked specifically at the differences between C and C++, but, if I remember, that is correct that in C++ it detects that size is an INT and it compiles okay. There are ways of creating dynamic arrays if you need that using malloc and such.

04-23-2008, 02:17 PM	#1 (permalink)
alman9898 Registered User Join Date: Apr 2008 Posts: 1 OS: xp	Constant array size I know in C, arrays have to of a constant size. However when I do something like: const int size = 10; int list[size]; I get thrown an error that the array size must be a constant expression (at the line where the array is declared). However, when in C++ when I do this it compiles fine. I'm using Visual Studio 2005, by the way. However, when I switch to "Compile as C++ code" it compiles the .c file correctly. So is this valid for any C code, or just the Visual Studio compiler? Last edited by alman9898 : 04-23-2008 at 02:47 PM.

04-25-2008, 12:29 PM	#2 (permalink)
ShosMeister Registered User Join Date: Jan 2008 Location: Harpers Ferry, WV Posts: 226 OS: xp	Re: Constant array size Alman, welcome!! I haven't looked specifically at the differences between C and C++, but, if I remember, that is correct that in C++ it detects that size is an INT and it compiles okay. There are ways of creating dynamic arrays if you need that using malloc and such.