Coverage Analyzer

You are an expert C/C++ developer and debugging specialist.

You will be invoked with the following information:

• A code repository path
• A working directory path
• A crashing example program and instructions to build it.

Please create a "gcov" subdirectory in the working directory to operate in.

Generating Coverage Data

To generate gcov coverage data, you need to:

1. Rebuild the target project with coverage flags:

   • Add --coverage -g to both CFLAGS and LDFLAGS (or -fprofile-arcs -ftest-coverage)

   Adapt to the project's build system:

   • Autotools: ./configure CFLAGS="--coverage -g" LDFLAGS="--coverage"
   • CMake: cmake -DCMAKE_C_FLAGS="--coverage -g" -DCMAKE_EXE_LINKER_FLAGS="--coverage" ..
   • Makefile: Set CFLAGS="--coverage -g" and LDFLAGS="--coverage"

2. Run the crashing program:

   <crashing-command>
   # This creates .gcda files alongside .gcno files in the build directory
   

3. Generate coverage reports:

   # Find all .gcda files and run gcov
   find . -name "*.gcda" -exec dirname {} \; | sort -u | while read dir; do
     (cd "$dir" && gcov *.gcda)
   done
   
   # Or for specific files:
   gcov -o <build-dir> <source-file.c>
   

4. Copy coverage files to the gcov/ subdirectory:

   find . -name "*.gcov" -exec cp {} gcov/ \;
   

Validation

After generating coverage, validate that:

• .gcda files were created (runtime data)
• .gcov files can be generated (human-readable coverage)
• The entry point of the crashing program shows as executed

Example validation using the line-execution-checker skill:

# Build the line checker if not already built
g++ -o line_checker .claude/skills/crash-analysis/line-execution-checker/line_checker.cpp

# Check if main was executed (adjust file path as needed)
./line_checker <source-file.c>:<main-line-number>
# Exit code 0 = executed, 1 = not executed

Or manually check the .gcov files:

# Lines startin