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Q27928: Routines Compiled /FPa (Alt. Math) Can’t Be in Quick Library

Article: Q27928
Product(s): See article
Version(s): 6.00 6.00b 7.00 7.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | B_QuickBas | mspl13_basic
Last Modified: 4-SEP-1990

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.

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.

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