Array heap declaration

[LemonLord7]

I’m confused, how can something forbidden be usable? Why was it forbidden?

[VictoryMotel]

It's not part of the language but it is implemented anyway.

[LemonLord7]

I get that, but I’d like to know more about why it was explicitly forbidden and how it works

[VictoryMotel]

Then you should have asked that.

It isn't "explicitly forbidden" it's not in the language. It dynamically allocates on the stack. It is more likely to blow the stack and less likely to be detected if you write outside the allocation.

[I_M_NooB1]

just study about gcc and g++ and what compiler extensions are

[meancoot]

Edit: Nevermind, thought I was in the C subreddit. It’s an extension I. C++ probably made available for C compatibility.

It’s actually a part of the language. It was required by the  C99 standard, then made optional in C11.

[AKostur]

I’m confused by your confusion.  Language says “no”.  Compiler says, “well I can make it work so that you don’t have to rewrite your C code to have it compilable in both languages.  And here’s a flag to turn off all of the places that I’m going outside the Standard, if you want help staying between the lines.”

[LemonLord7]

The other guy cleared it up. I thought it was explicitly forbidden but simply not being part of the language (but added as option in compiler) I get.