Re: Treat undeclared macro constants as zero?
On Tue, 18 Aug 2009 18:00:54 -0700 (PDT), Sin Jeong-hun
<typingcat@gmail.com> wrote:
Hello.
Is it possible to configure the preprocessor so that when it
encounters some undeclared macro constant in the C code then it
replaces it with zero? The situation is complicated but basically we
have some master "configuration file" which is actually a c file that
has all values as macro constants. Each time someone adds a new macro
constant to the master configuration file, we must update all other
branch configuration files accordingly by putting zeros for the
constant, because zero means it's not supported. So, if the
preprocessor replaces undeclared macro constants with zero
automatically, then it would be a lot easier.
I'm not sure what you're asking. If a macro isn't declared, how is the
compiler supposed to know it's a macro and not, say, a misspelled variable?
Note that inside preprocessor directives like #if, an undeclared macro is
treated as 0.
--
Doug Harrison
Visual C++ MVP
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