C_DEFINES

Use the C_DEFINES macro to specify the switches that you want passed to the C/C++ compiler and to the Microsoft interface description language compiler (MIDL).

Typically, these switches are compiler defined (/D) directives.

For example, to define DEBUG_BUILD to the compiler, specify:

C_DEFINES = /DDEBUG_BUILD

In a Sources file, you can add text to the C_DEFINES macro without losing its original content. For example, to define UNICODE to the compiler in addition to any existing C_DEFINES switches, you could specify:

C_DEFINES = $(C_DEFINES) /DUNICODE 

Although there is no limit to the number of /D directives that are specified through the C_DEFINES macro, be aware that the macro is passed to the compiler and it also is passed to the resource compiler. Therefore, , you cannot put compiler optimization, platform-specific or tool-specific switches in the C_DEFINES macro because they are not handled by the resource compiler.

For compiler optimization, platform-specific or tool-specific switches, use one of the following macros in your Sources file:

• MSC_OPTIMIZATION

• MSC_WARNING_LEVEL

• USER_C_FLAGS

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Build date: 5/3/2011