error C2143: syntax error : missing ';' before 'type'

When programming in Visual Studio, if you happen to run across this error while trying to compile C code, one thing to check on is whether or not you're declaring your local variables inline.  For whatever reason, Visual Studio hates this and issues a syntax error for the next line of code.  One that's of no use whatsoever in helping to figure out what to do.

So, for example, if you have a function like:

int foo(int x)
{
    assert(x != 0);
    int y = 4/x;
    return y;
}

You would need to rewrite your code like this:

int foo(int x)
{
    int y;
    assert(x != 0);
    y = x/4;
    return y;
}

Strange but true.  I suspect there's an option somewhere to turn off the strictness of the compiler, but I haven't found it.

Comments

[Johann]

Hello,

I found an other cause on http://rt.cpan.org/Public/Bug/Display.html?id=12925

"microsoft C compiler wants all variables declared at top of function", which is what is being done in the second example.
That worked perfect for me.

[Martin v. Löwis]

It's no surprise that Microsoft's compiler wants the variables at the beginnig of the function: Standard C wants them there.

Atleast, this is what C89 defines. C99 allows variable declarations also in the middle of a function.

[John]

I don't think is necessarily at the beginning of the function, I think the variables have to be at the beginning of the scope you are in, like this

int function ( )
{
int x = 1;
int y = 0;
if( x )
{
int z = 0; //this is ok
}
}

[Shane Tuohy]

The problem is you are using a C file. This means the compiler implements strict C rules. If you change your source file to a cpp type file, you will use the C++ compiler which is myuch more flexible

[Stefan___]

I was compiling a simple C program and came across this post (when the above described error came up for me) and I agree with @Johann and @Shane Tuohy both are true; just tested them :)