Routines Compiled /FPa (Alt. Math) Can't Be in Quick Library (27928)

SUMMARY

The linker error message "L2025: Symbol defined more than once" occurs when you attempt to create a Quick library (LINK /Q) from .OBJ modules that were compiled with the alternate math package (BC /FPa) option.

Routines compiled with BC /FPa (the alternate math package switch) cannot be placed into a Quick library because the QB.EXE or QBX.EXE environment does not support the use of the alternate math package. The QuickBasic and QuickBasic extended environments support only the IEEE coprocessor-emulation math package (/FPi). The alternate math package (/FPa) is only supported in compiled EXE programs.

This information applies to the QB.EXE environment supplied with Microsoft Basic Compiler versions 6.00 and 6.00b for MS-DOS, and to the QBX.EXE environment supplied with Microsoft Basic Professional Development System (PDS) versions 7.00 and 7.10.

MORE INFORMATION

The purpose of the alternate floating-point math package is to provide faster floating-point calculations on computers that do not have a coprocessor. The alternate math package is significantly faster than the IEEE coprocessor-emulation math package when run on a computer without a coprocessor installed.

Note that the alternate math package is about 50 percent slower than the Microsoft Binary Format (MBF) floating-point math found in the noncoprocessor version of QuickBasic versions 3.00 and earlier. (QuickBasic versions 4.00, 4.00b, and 4.50, Microsoft Basic Compiler versions 6.00 and 6.00b, and Microsoft PDS versions 7.00 and 7.10 only offer support for the older MBF math with a /MBF compiler option and some MBF numeric conversion functions. These Basic versions have adopted IEEE and alternate math to be compatible with the other Microsoft language products [FORTRAN, Pascal, and C] and to support the math coprocessor.)

For the greatest speed, applications should be compiled with the BC /FPi switch and run on a computer with a coprocessor installed.