Q37646: FOR…NEXT with 32767 or -32768 Index Fails to Stop Unless /d
Article: Q37646 Product(s): See article Version(s): 4.00 4.00b 4.50 Operating System(s): MS-DOS Keyword(s): ENDUSER | | mspl13_basic Last Modified: 21-DEC-1989 If you use an integer for a FOR...NEXT loop counter, and the top of the loop is 32767 (when STEP is positive) or the bottom of the loop is -32768 (when STEP is negative), an overflow error will be correctly generated by QB.EXE or by the EXE compiled with /d. Without the /d, the loop does not stop at the top/bottom; it wraps around and executes indefinitely. The problem occurs because overflow checking is only done when /d compiler switch is specified. The following is a code example: This program never finishes the FOR NEXT loop when compiled without /d. DEFINT A-Z FOR X = 1 TO 32767 IF X MOD 100 = 0 THEN PRINT X NEXT X
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