8.3.1 Enhanced tcov Analysis

To use tcov, compile with -xprofile=tcov. When the program is run, coverage data is stored in program.profile/tcovd, where program is the name of the executable file. (If the executable were a.out, a.out.profile/tcovd would be created.)

Run tcov -x dirname source_files to create the coverage analysis merged with each source file. The report is written to file.tcov in the current directory.

Running a simple example:

demo% f95 -o onetwo -xprofile=tcov one.f two.f
demo% onetwo
       ... output from program
demo% tcov -x onetwo.profile one.f two.f
demo% cat one.f.tcov two.f.tcov
                       program one
      1 ->             do i=1,10
     10 ->                   call two(i)
                       end do
      1 ->             end
       .....etc
demo%

Environment variables $SUN_PROFDATA and $SUN_PROFDATA_DIR can be used to specify where the intermediary data collection files are kept. These are the *.d and tcovd files created by old and new style tcov, respectively.

These environment variables can be used to separate the collected data from different runs. With these variables set, the running program writes execution data to the files in $SUN_PROFDATA_DIR/$SUN_PROFDATA/.

Similarly, the directory that tcov reads is specified by tcov -x $SUN_PROFDATA. If $SUN_PROFDATA_DIR is set, tcov will prepend it, looking for files in $SUN_PROFDATA_DIR/$SUN_PROFDATA/, and not in the working directory.

Each subsequent run accumulates more coverage data into the tcovd file. Data for each object file is zeroed out the first time the program is executed after the corresponding source file has been recompiled. Data for the entire program is zeroed out by removing the tcovd file.

For the details, see the tcov(1) man page.