Rule 3.1 - Hyperlinks in comments?

[Andrew Banks]

Cross-post from the MISRA C/C++ LinkedIn group

Is there any chance MISRA could alter Rule 3.1 to allow common hyperlinks in C comments such that a Deviation isn't required:

Code:

/*
* See https://somewhere.over.the.rainbow/way/up/high.htm
*/

I use direct references to RFCs in source files that allow clicking in Visual Studio to open up a browser at the relevant spec. MISRA sees this as evil. If https: or http: occurs before //, then there isn't much confusion about commenting...

The (perfectly sound) Rationale for the Rule is to detect missing */ comment terminators.

There is already an Exception to permit // within a */ comment... so a further Exception to permit hyperlinks of the form http://, https://, ftp:// or ftps:// (without requiring a Deviation) seems reasonable?

[misra-c]

C90 and C99 strictly conforming compilers have well-defined behaviour for // within a /* comment. However many compilers are non strictly conforming and a variety of behaviour has been observed.

We suggest two methods for including hyperlinks within a comment.

1. In C99, the use of // within a // comment is permitted in the Exception to this rule.
   
   Code:

   // See  https://somewhere.over.the.rainbow/way/up/high.htm
   
   
2. Create a deviation/permit which permits the inclusion of // within a /* comment after checks have performed on the compiler that is used to confirm that such inclusion behaves as expected.

[misra-c]

MISRA C:2012 Amendment 4 (published Mar 2023) adds an exception for URIs

This has been consolidated into MISRA C:2023