DEFINE_SYMBOL¶
Define a symbol when compiling this target’s sources.
DEFINE_SYMBOL sets the name of the preprocessor symbol defined when compiling sources in a shared library. If not set here then it is set to target_EXPORTS by default (with some substitutions if the target is not a valid C identifier). This is useful for headers to know whether they are being included from inside their library or outside to properly setup dllexport/dllimport decorations.