Floating-Point Routines Are Not Reentrant

ID: Q40587

6.00 6.00a 6.00ax 7.00 | 1.00 1.50 1.51 1.52

MS-DOS                 | WINDOWS

kbprg

The information in this article applies to:

The C Run-time (CRT), included with:

    - Microsoft C for MS-DOS, versions 6.0, 6.0a, and 6.0ax
    - Microsoft C/C++ for MS-DOS, version 7.0
    - Microsoft Visual C++ for Windows, versions 1.0, 1.5, 1.51, and 1.52

The Microsoft C run-time library math routines are nonnreentrant and accordingly do not save and restore the registers used on the 80x87 floating-point coprocessor.

If you want to develop a program that requires the math coprocessor to be reentrant, you must provide your own routines that save and restore the registers of the coprocessor.

Additional reference words: kbinf 6.00 6.00a 6.00ax 7.00 1.00 1.50 KBCategory: kbprg KBSubcategory: CRTIss Keywords : kb16bitonly

Last Reviewed: July 18, 1997