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handling of defined() conditions nested in function like macros #75
Description
defined() conditions in function like macros are not handled correctly.
minimal example, which expects __FOO__ to be defined or not.
#include <stdio.h>
#define macro(var) (defined(__ ## var ## __))
int main(void) {
#if macro(FOO)
printf("__FOO__ defined\r\n");
#else
printf("__FOO__ not defined\r\n");
#endif
return 0;
}
preprocessing with gcc gives:
# gcc -D__FOO__ -E test.c
[...]
int main (void) {
printf("__FOO__ defined\r\n");
return 0;
}
preprocessing with simplecpp gives
# simplecpp -D__FOO__ -E test.c
int main ( void ) {
printf( "__FOO__ not defined\r\n" ) ;
return 0 ;
}
The real world code i encountered the problem with is in parts.h of atmel software framework. They expect the user to define the chip, software is being compiled for, as __chipname__ and derive family, series and product line from this.
short excerpt to clarify:
#define SAM_PART_IS_DEFINED(part) (defined(__ ## part ## __))
[...]
/* SAM4S series */
#define SAM4S16 ( \
SAM_PART_IS_DEFINED(SAM4S16B) || \
SAM_PART_IS_DEFINED(SAM4S16C) \
)
[...]
/* SAM4S Family */
#define SAM4S (SAM4S2 || SAM4S4 || SAM4S8 || SAM4S16 || SAM4SA16 || SAM4SD16 || SAM4SD32)
[...]
/* SAM product line */
#define SAM (SAM3S || SAM3U || SAM3N || SAM3XA || SAM4S || SAM4L || SAM4E || \
SAM0 || SAM4N || SAM4C || SAM4CM || SAM4CP || SAMG)
So if __SAM4S16C__ was defined by -D__SAM4S16C__ the macros SAM4S16, SAM4S and SAM are expected to be set to 1
Activity
firewave commentedon Jul 3, 2025
It now reports: