[cfe-dev] [RFC] new checker: function pointer parameter can be const

[Daniel Marjamäki]

Hello!

I am working on a new checker; function parameter can be const.

I plan to warn when:
 * a function parameter is not const
 * the function parameter is a pointer
 * it is dereferenced in the function (otherwise there will be -Wunused-parameter warnings)
 * the pointer address is not taken
 * the data is not written

Example code:

    int x;
    void warn(int *p) { x = *p; }   // <- Warning
    void dontwarn(int *p) { *p = 0; }  // <- No warning, data is written

My checker works a bit like the -Wunused-parameter warning. I add a flag to Decl that says if there is non-const usage.

I attach a proof-of-concept patch. It does not work well yet but shows how I intend to implement this.

Best regards,
Daniel Marjamäki

..................................................................................................................
Daniel Marjamäki Senior Engineer
Evidente ES East AB  Warfvinges väg 34  SE-112 51 Stockholm  Sweden

Mobile:                 +46 (0)709 12 42 62
E-mail:                 Daniel.Marjamaki at evidente.se

www.evidente.se
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