Q35885: LONG INTEGER Overflow Is Not Detected in EXE

Article: Q35885
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist4.00 buglist4.00b buglist4.50 B_BasicCom | mspl13_basic
Last Modified: 20-SEP-1990

The program below, when run in the QB.EXE or QBX.EXE editor, correctly
generates an "Overflow" message. However, the EXE program incorrectly
prints a -2 (even when compiled with the /D (debug) option).

Microsoft has confirmed this to be a problem in QuickBASIC versions
4.00, 4.00b, and 4.50; in Microsoft BASIC Compiler versions 6.00 and
6.00b (buglist6.00, buglist6.00b) for MS-DOS and MS OS/2; and in
Microsoft BASIC Professional Development System (PDS) versions 7.00
and 7.10 (buglist7.00, buglist7.10) for MS-DOS and MS OS/2. We are
researching this problem and will post new information here as it
becomes available.

The following is a code example:

   a& = 2147483647     ' Largest positive long integer
   b& = 2
   x& = a& * b&
   PRINT x&            ' EXE version prints a -2

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