sqlite-with-gcov: Task instruction is ambiguous about build directory

[kehao95]

Summary

The instruction for sqlite-with-gcov task is ambiguous, leading agents to a reasonable but incorrect interpretation.

Current Instruction

Compile SQLite in /app/sqlite with gcov instrumentation and make it available in the PATH.

The Ambiguity

"Compile SQLite in /app/sqlite" can be interpreted two ways:

Interpretation	Meaning	Typical Approach
A: "in" = build directory	Build inside /app/sqlite	cd /app/sqlite && ./configure && make
B: "in" = install prefix	Install SQLite to /app/sqlite	./configure --prefix=/app/sqlite && make install

Interpretation B is natural because:

1. "make it available in the PATH" suggests installation
2. Standard software installation uses ./configure --prefix=X && make install
3. Sources are typically extracted to /tmp, built there, then installed to target

Verifier Expectation

The verifier expects interpretation A — it checks for .gcno and .gcda files inside /app/sqlite:

# From tests/test_outputs.py
for root, _, files in os.walk("/app/sqlite"):
    gcno_files.extend([...f for f in files if f.endswith(".gcno")])

This only works if the build directory is /app/sqlite, not just the install prefix.

Agent Behavior

An agent (Claude Sonnet 4) chose interpretation B:

1. Extracted source to /tmp/sqlite
2. Configured with --prefix=/app/sqlite
3. Built with CFLAGS="--coverage" — correct gcov flags
4. Ran make install to /app/sqlite/bin/
5. Verified binary has 7476 gcov symbols — instrumentation IS present
6. Cleaned up /tmp/sqlite (which contained .gcno files)

The binary is gcov-instrumented, but .gcno files aren't in /app/sqlite.

Suggested Fix

Make the instruction explicit about the build directory requirement:

Compile SQLite with build directory at /app/sqlite with gcov instrumentation and make it available in the PATH. The .gcno files from compilation must remain in /app/sqlite.

Or alternatively, update the verifier to check for gcov instrumentation in a way that doesn't depend on build directory location (e.g., check for gcov symbols in the binary).