> gcc/ChangeLog:
>
> * doc/gcov.texi: Add MC/DC section.
OK,
thanks!
Honza
> ---
> gcc/doc/gcov.texi | 72 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 72 insertions(+)
>
> diff --git a/gcc/doc/gcov.texi b/gcc/doc/gcov.texi
> index dc79bccb8cf..a9221738cce 100644
> --- a/gcc/doc/gcov.texi
> +++ b/gcc/doc/gcov.texi
> @@ -917,6 +917,78 @@ of times the call was executed will be printed. This
> will usually be
> 100%, but may be less for functions that call @code{exit} or @code{longjmp},
> and thus may not return every time they are called.
>
> +When you use the @option{-g} option, your output looks like this:
> +
> +@smallexample
> +$ gcov -t -m -g tmp
> + -: 0:Source:tmp.cpp
> + -: 0:Graph:tmp.gcno
> + -: 0:Data:tmp.gcda
> + -: 0:Runs:1
> + -: 1:#include <stdio.h>
> + -: 2:
> + -: 3:int
> + 1: 4:main (void)
> + -: 5:@{
> + -: 6: int i, total;
> + 1: 7: total = 0;
> + -: 8:
> + 11: 9: for (i = 0; i < 10; i++)
> +condition outcomes covered 2/2
> + 10: 10: total += i;
> + -: 11:
> + 1*: 12: int v = total > 100 ? 1 : 2;
> +condition outcomes covered 1/2
> +condition 0 not covered (true)
> + -: 13:
> + 1*: 14: if (total != 45 && v == 1)
> +condition outcomes covered 1/4
> +condition 0 not covered (true)
> +condition 1 not covered (true false)
> + #####: 15: printf ("Failure\n");
> + -: 16: else
> + 1: 17: printf ("Success\n");
> + 1: 18: return 0;
> + -: 19:@}
> +@end smallexample
> +
> +For every condition the number of taken and total outcomes are
> +printed, and if there are uncovered outcomes a line will be printed
> +for each condition showing the uncovered outcome in parentheses.
> +Conditions are identified by their index -- index 0 is the left-most
> +condition. In @code{a || (b && c)}, @var{a} is condition 0, @var{b}
> +condition 1, and @var{c} condition 2.
> +
> +An outcome is considered covered if it has an independent effect on
> +the decision, also known as masking MC/DC (Modified Condition/Decision
> +Coverage). In this example the decision evaluates to true and @var{a}
> +is evaluated, but not covered. This is because @var{a} cannot affect
> +the decision independently -- both @var{a} and @var{b} must change
> +value for the decision to change.
> +
> +@smallexample
> +$ gcov -t -m -g tmp
> + -: 0:Source:tmp.c
> + -: 0:Graph:tmp.gcno
> + -: 0:Data:tmp.gcda
> + -: 0:Runs:1
> + -: 1:#include <stdio.h>
> + -: 2:
> + 1: 3:int main()
> + -: 4:@{
> + 1: 5: int a = 1;
> + 1: 6: int b = 0;
> + -: 7:
> + 1: 8: if (a && b)
> +condition outcomes covered 1/4
> +condition 0 not covered (true false)
> +condition 1 not covered (true)
> + #####: 9: printf ("Success!\n");
> + -: 10: else
> + 1: 11: printf ("Failure!\n");
> + -: 12:@}
> +@end smallexample
> +
> The execution counts are cumulative. If the example program were
> executed again without removing the @file{.gcda} file, the count for the
> number of times each line in the source was executed would be added to
> --
> 2.39.2
>
