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.