-q32, -q64

Description

Selects either 32-bit or 64-bit compiler mode.

Syntax

Read syntax diagramSkip visual syntax diagram        .-32-.
>>- -q--+-64-+-------------------------------------------------><

Notes

The -q32 and -q64 options override the compiler mode set by the value of the OBJECT_MODE environment variable, if it exists. If this option is not explicitly specified on the command line, and the OBJECT_MODE environment variable is not set, the compiler will default to 32-bit output mode.

If the compiler is invoked in 64-bit mode, the __64BIT__ preprocessor macro is defined.

Use -q32 and -q64 options, along with the -qarch and -qtune compiler options, to optimize the output of the compiler to the architecture on which that output will be used. Refer to Acceptable compiler mode and process or architecture combinationsfor valid combinations of the -q32, -q64, -qarch, and -qtune compiler options. In 64-bit mode, -qarch=com is treated the same as -qarch=ppc.

Using -qarch=ppc or any ppc family architecture with -qfloat=hssngl or -qfloat=hsflt may produce incorrect results on rs64II or future systems.

Example

To specify that the executable program testing compiled from myprogram.c is to run on a computer with a 32-bit PowerPC(R) architecture, enter:

xlc -o testing myprogram.c -q32 -qarch=ppc

Important!

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