Line Execution Checker
Purpose
Fast tool to check if specific source lines were executed during test runs.
Tool: line-checker
Build
Always build fresh from this skill's line_checker.cpp, into a scratch
directory YOU create — never into (or from) the coverage/build directory.
That directory is written by the instrumented target's own build and run,
so any pre-existing line-checker found there could have been planted by
the analysed program to forge coverage verdicts; never execute one.
bashCHECKER_DIR=$(mktemp -d) g++ -O3 -std=c++17 line_checker.cpp -o "$CHECKER_DIR/line-checker"
Usage
bash# Single line (from the coverage data directory) "$CHECKER_DIR/line-checker" file.c:42 # Multiple lines "$CHECKER_DIR/line-checker" file.c:42 main.c:100 util.c:55
Output
file.c:42 EXECUTED (5 times) main.c:100 NOT EXECUTED util.c:55 EXECUTED (12 times)
Exit Codes
- 0: All lines executed
- 1: One or more lines NOT executed
- 2: Error
Prerequisites
Coverage data must exist from prior test run with --coverage flag.
When User Asks
"Was line X of file.c executed?" or "Check if these lines were covered"
Steps
- Verify
.gcdafiles exist:find . -name "*.gcda" -print -quit - Build the tool fresh into a scratch dir (see Build above — never
reuse a
line-checkerbinary found in the coverage/build tree):CHECKER_DIR=$(mktemp -d) && g++ -O3 -std=c++17 line_checker.cpp -o "$CHECKER_DIR/line-checker" - Run:
"$CHECKER_DIR/line-checker" file.c:X - Report result to user
Example Interaction
User: "Was line 127 in parser.c executed?"
bash"$CHECKER_DIR/line-checker" parser.c:127 # Output: parser.c:127 EXECUTED (3 times)
Response: "Yes, line 127 was executed 3 times during testing."
