Code compiles fine on GCC but loads of error on VC2010 - c

Question

I made a number guessing game in C that compiles fine with GCC 4.7.1. But it gives a lot of error with VC2010. Mostly syntax error issues. I don't know why it gives these errors as I've compiled many other C sources with VC2010 without these errors.
I compile it with VC (Command Line) with the command: cl guessgame.c
VC gives the following errors:
Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.30319.01 for
Copyright (C) Microsoft Corporation. All rights reserved.
guessgame.c
guessgame.c(8) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(9) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(10) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(11) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(12) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(13) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(14) : error C2143: syntax error : missing ';' before 'type'
guessgame.c(20) : error C2065: 'chances' : undeclared identifier
guessgame.c(21) : error C2065: 'randRangeX' : undeclared identifier
guessgame.c(21) : error C2065: 'randRangeY' : undeclared identifier
guessgame.c(23) : error C2065: 'i' : undeclared identifier
guessgame.c(23) : error C2065: 'chances' : undeclared identifier
guessgame.c(23) : error C2065: 'i' : undeclared identifier
guessgame.c(23) : error C2065: 'i' : undeclared identifier
guessgame.c(25) : error C2065: 'chances' : undeclared identifier
guessgame.c(25) : error C2065: 'i' : undeclared identifier
guessgame.c(26) : error C2065: 'userAns' : undeclared identifier
guessgame.c(28) : error C2065: 'userAns' : undeclared identifier
guessgame.c(28) : error C2065: 'randomNumber' : undeclared identifier
guessgame.c(30) : error C2065: 'chances' : undeclared identifier
guessgame.c(30) : error C2065: 'i' : undeclared identifier
guessgame.c(36) : error C2065: 'wrong_guesses' : undeclared identifier
guessgame.c(39) : error C2065: 'wrong_guesses' : undeclared identifier
guessgame.c(41) : error C2065: 'randomNumber' : undeclared identifier
Here is the code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main()
{
srand(time(NULL));
int randomNumber = (rand() % 245)+5;
int userAns;
int randRangeX = randomNumber-((rand() % 3)+5);
int randRangeY = randomNumber+((rand() % 3)+5);
int chances = 3;
int wrong_guesses = 0;
int i;
printf("Number guessing game v1.1.\n");
printf("Copyright(c) 2013 - Ahnaf Tahmid.\n");
printf("-----------------------------------\n\n");
printf("Rules: 1) Guess the number.\n");
printf(" 2) You have %d chances.\n\n", chances);
printf("The number is between %d and %d.", randRangeX, randRangeY);
for(i = chances; i >= 1; i--)
{
printf("\nGuess %d: ", (chances-i)+1);
scanf("%d", &userAns);
while(getchar() != '\n');
if(userAns == randomNumber)
{
printf("\nGood guess! You guessed it in %d turn(s).\n", (chances-i)+1);
break;
}
else
{
printf("Aww, bad guess.\n");
wrong_guesses += 1;
}
}
if(wrong_guesses == 3)
{
printf("\nGame Over!\n\nThe answer was %d.\n", randomNumber);
}
getch();
return 0;
}

Answer 1

VC2010 supports C89 which requires that variables be declared at the start of their scope block. You can build with both compilers if you move the srand call after your variable declarations and delay initialising the variables which depend on rand().
int main()
{
int randomNumber;
int userAns;
int randRangeX;
int randRangeY;
int chances = 3;
int wrong_guesses = 0;
int i;
srand(time(NULL));
randomNumber = (rand() % 245)+5;
randRangeX = randomNumber-((rand() % 3)+5);
randRangeY = randomNumber+((rand() % 3)+5);

Answer 2

In C89, all variables have to be declared in the beginning of a block. This has been removed in C99.
But VC2010 doesn't support C99. So you have to put
srand(time(NULL));
after all the declaration of variables.
Reference:
C89 §3.6.2 Compound statement, or block
Syntax
compound-statement:
{ declaration-list opt statement-list opt }
declaration-list:
declaration
declaration-list declaration
statement-list:
statement
statement-list statement
Note that in C89, declaration-list has to be before statement -list in a block.
C99 §6.8.2 Compound statement
Syntax
compound-statement:
{ block-item-list_opt }
block-item-list:
block-item
block-item-list block-item
block-item:
declaration
statement
In C99, declaration and statement can be mixed.

Answer 3

An alternative approach to solve the issue pointed out by the other answers would be to open a new scope:
int main()
{
srand(time(NULL));
{
int randomNumber = (rand() % 245)+5;
int userAns;
int randRangeX = randomNumber-((rand() % 3)+5);
int randRangeY = randomNumber+((rand() % 3)+5);
int chances = 3;
int wrong_guesses = 0;
int i;
...