fix overflow on bigint platforms (close #42)

Test.hx

@@ -21,15 +21,8 @@ class Test extends TestCase {
 	function test():Void {
 		assertScript("0",0);
 		assertScript("0xFF", 255);
-		#if !(php || python)
-			#if haxe3
-			assertScript("0xBFFFFFFF", 0xBFFFFFFF);
-			assertScript("0x7FFFFFFF", 0x7FFFFFFF);
-			#elseif !neko
-			assertScript("n(0xBFFFFFFF)", 0xBFFFFFFF, { n : haxe.Int32.toNativeInt });
-			assertScript("n(0x7FFFFFFF)", 0x7FFFFFFF, { n : haxe.Int32.toNativeInt } );
-			#end
-		#end
+		assertScript("0xBFFFFFFF", 0xBFFFFFFF);
+		assertScript("0x7FFFFFFF", 0x7FFFFFFF);
 		assertScript("-123",-123);
 		assertScript("- 123",-123);
 		assertScript("1.546",1.546);

hscript/Parser.hx

@@ -983,7 +983,7 @@ class Parser {
 							// in case of '...'
 							if( exp == 10 && readChar() == 46 ) {
 								push(TOp("..."));
-								var i = Std.int(n);
+								var i = Std.int(n) & 0xFFFFFFFF;
 								return TConst( (i == n) ? CInt(i) : CFloat(n) );
 							}
 							invalidChar(char);
@@ -1006,7 +1006,7 @@ class Parser {
 								n = (n << 4) + (char - 87);
 							default:
 								this.char = char;
-								return TConst(CInt(n));
+								return TConst(CInt(n & 0xFFFFFFFF));
 							}
 						}
 						#else