29-08-2006, 03:50 PM
Quote:Code:#define M1 ;
This macro breaks rule 19.4. Macro expanding to Null statement is not allowed.
Code:#define M2
#define M3 /* comment */
This macro expands to no body, and is therefore not prohibited by 19.4.
A comment in a macro definition is removed by the pre-processor. Rule 14.3 applied before
Pre-processing. Treatment of M2 and M3 is identical.
Code:M1
Since definition of M1 macro was invalid, its use is already a violation.
Code:M2;
M3;
After pre-processing, these are both Null statements. Before pre-processing, there are characters before the Null statement. This is not allowed by 14.3.
Re-posted under offical user name only.
Posted by and on behalf of the MISRA C Working Group