Question

Lines starting with sign ‘%’ should be passed as is in output file,
but is such lines have some CPP macros, those macros are expanded as well:

Source (test.x):

#ifdef ONE
#warning "ONE is defined"
#else
#warning "NO ONE!!!!!1111"
#endif

%
% hello, ONE
%

Running rpcgen:

# rpcgen test.x -DONE
test.x:2:2: warning: #warning "ONE is defined" [-Wcpp]
test.x:2:2: warning: #warning "ONE is defined" [-Wcpp]
test.x:2:2: warning: #warning "ONE is defined" [-Wcpp]
test.x:2:2: warning: #warning "ONE is defined" [-Wcpp]

Result (test.h):

/*
 * Please do not edit this file.
 * It was generated using rpcgen.
 */

#ifndef _TEST_H_RPCGEN
#define _TEST_H_RPCGEN

#include <rpc/rpc.h>


#ifdef __cplusplus
extern "C" {
#endif


 hello, 1


#ifdef __cplusplus
}
#endif

#endif /* !_TEST_H_RPCGEN */

So “ONE” is replaced with “1”, but it is desirable leave it as is
(consider “#ifdef ONE” in resulting test.h)

It there any way to aviod it?

Answer 1

So, I have a workaroud with CPP wrapper:

1. somedir/cpp <- wrapped which undefines problematic macros. For example:

   #!/bin/sh

   exec /usr/bin/cpp -U_LP64

2. Run rpcgen as rpcgen -Y somedir