C-style Cast Problem

I'm converting a C program written for Solaris to a Windows 32 console program using Visual Studio 2005.

In my t_main function (found in test1.cpp), the following is declared:

Code:

MOLECULE *m = NULL;

When I try to compile, I get the following error in my initmole.cpp page:

Code:

 error C2440: '=' : cannot convert from 'int *' to 'MOLECULE *'
        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast

I'm pretty sure that I have to perform a cast on molecule *m in initmole.cpp. However, m is an array/struct so I have no idea on how to cast it. Below is
the code for initmole.cpp. How/where would I want to perform a cas?

Code:

MOLECULE *InitMol( void )
{
   MOLECULE *m;
  
   if ( (m = malloc( sizeof( *m ) )) == NULL ) { //this where it errors out
	  return( NULL );
   }

   m->N_Hydro = -1;
   m->N_Atoms =  0;
   m->N_Bonds =  0;
   m->N_Comps =  0;
   return( m );
}

I think it might be:

Code:

m = (MOLECULE*)malloc( sizeof( *m ) ) == NULL

Thank you laserlight for your reply.

I tried your suggestion, however now its giving the error:

Code:

error C2440: '=' : cannot convert from 'bool' to 'MOLECULE *'

Oops, I did not properly modify your code snippet. It should be:

Code:

if ( (m = (MOLECULE*)malloc( sizeof( *m ) )) == NULL ) {
    return( NULL );
}

Thank you so much, it worked!!! I'll study it and try to get a grasp on what that actually did.

Have a nice day

Well if you're really converting it to C++ (as opposed to merely accepting the filenames VC++ gives you and pretending that it's still C), then you should be converting all your malloc/free calls into new/delete.