1 files changed, 139 insertions, 3 deletions
diff --git a/test/tx/cmake/coverage.sh b/test/tx/cmake/coverage.sh
index 6dda78b3..32d466b7 100755
--- a/test/tx/cmake/coverage.sh
+++ b/test/tx/cmake/coverage.sh
@@ -14,6 +14,142 @@
 set -e
 
 cd $(dirname $0)
-mkdir -p coverage_report/$1
-gcovr --object-directory=build/$1/threadx/CMakeFiles/threadx.dir/common/src -r build/$1 -f ../../../common/src --xml-pretty --output coverage_report/$1.xml
-gcovr --object-directory=build/$1/threadx/CMakeFiles/threadx.dir/common/src -r build/$1 -f ../../../common/src --html --html-details --output coverage_report/$1/index.html
+
+# gcov reads a data format tied to the compiler that produced it, so gcov has to match
+# the gcc that built the objects. Since cmake/linux.cmake began honouring CC, taking
+# whatever gcov happens to be first on PATH is no longer safe: building with gcc-14 and
+# reading with gcov-13 gives "version 'B42*', prefer 'B33*'" from gcov, and gcovr turns
+# that into "GCOV returncode was 3" and exits 64. The tests pass and then the coverage
+# step fails with a Python traceback, which reads like a coverage bug rather than a
+# toolchain mismatch.
+#
+# So derive gcov from CC rather than asking the caller to remember both. GCOV still
+# overrides, for a toolchain that does not follow the gcc/gcov naming.
+: "${CC:=gcc}"
+if [ -z "${GCOV:-}" ]; then
+    cc_base=$(basename "$CC")
+    case "$cc_base" in
+        gcc*) GCOV="gcov${cc_base#gcc}" ;;
+        *)    GCOV="gcov" ;;
+    esac
+fi
+
+if ! command -v "$GCOV" >/dev/null 2>&1; then
+    echo "coverage.sh: '$GCOV' not found, derived from CC='$CC'." >&2
+    echo "Install it, or set GCOV to the gcov matching that compiler." >&2
+    exit 1
+fi
+
+# The repository root, needed by every mode below. It has to be absolute: see the
+# note on the per-configuration paths further down.
+repo_root=$(cd ../../.. && pwd)
+filter=$repo_root/common/src
+
+# --merge unions the per-configuration reports into the one number that means
+# something. Each configuration writes an intermediate JSON beside its XML, and
+# this pass adds them all together.
+#
+# Reporting five separate percentages instead would invite a reader to average
+# them, and an average is not a coverage figure -- a line covered only by
+# trace_build is covered, and only the union says so.
+#
+# Do not be alarmed when the merged percentage is lower than the single
+# configuration this used to report. That is the point: the denominator now
+# includes code the old report never counted at all, because it was compiled out
+# of the only instrumented build.
+if [ "$1" = "--merge" ]; then
+    shopt -s nullglob
+    tracefiles=(coverage_report/per_configuration/*.json)
+    shopt -u nullglob
+    if [ ${#tracefiles[@]} -eq 0 ]; then
+        echo "coverage.sh --merge: no JSON in coverage_report/per_configuration/." >&2
+        echo "Run the suites with TX_COVERAGE=ON first." >&2
+        exit 1
+    fi
+
+    add_args=()
+    for t in "${tracefiles[@]}"; do
+        add_args+=(--add-tracefile "$t")
+    done
+
+    mkdir -p coverage_report/merged
+    gcovr -r "$repo_root" "${add_args[@]}" --xml-pretty --output coverage_report/merged.xml
+    gcovr -r "$repo_root" "${add_args[@]}" --html --html-details --output coverage_report/merged/index.html
+
+    if ! grep -q "<class " coverage_report/merged.xml; then
+        echo "coverage.sh --merge: the merged report contains no files." >&2
+        exit 1
+    fi
+
+    # Named, not just counted. coverage_report/ is not cleaned between runs, so a
+    # tracefile left by an earlier run of a different set of configurations would
+    # otherwise be merged in without anything saying so.
+    echo "coverage.sh --merge: ThreadX, ${#tracefiles[@]} configuration(s):"
+    for t in "${tracefiles[@]}"; do
+        echo "    $(basename "$t" .json)"
+    done
+    exit 0
+fi
+
+# gcovr is given three paths below, and each of them has to be absolute, for a
+# different reason.
+#
+# -r is the repository root rather than the build directory, so the report names
+# files the way the repository does -- "common/src/tx_block_allocate.c" instead
+# of "/home/runner/work/threadx/threadx/common/src/tx_block_allocate.c". With -r
+# inside build/, gcovr cannot express the sources relative to it, because they
+# are outside it, and falls back to absolute paths. Those paths then differ on
+# every machine and disagree with the <source> element written beside them in
+# the same file, so anything that maps coverage back to the repository -- PR
+# annotations, Codecov, SonarQube -- cannot follow them.
+#
+# Both -r and -f must be absolute. "-r ../../.. -f common/src" produces a report
+# containing zero files and exits 0, which is the worst failure mode available
+# here: a green run carrying an empty report. Measured, not assumed. repo_root
+# and filter are set above, before the merge mode, because it needs them too.
+
+# This is what actually scopes the report to one build configuration, and it is
+# the positional search path -- not --object-directory, which used to be here
+# and was doing nothing at all. That flag tells gcovr how to get from a gcda
+# file back to the compiler's working directory; it does not restrict which gcda
+# files are found. Pointed at an empty directory it still produced the full
+# 177-file report, because gcovr searches -r as well.
+#
+# That matters more now than it did before. While -r was build/$1 it happened to
+# constrain the search to this configuration by accident. -r is the repository
+# root now, and every configuration's gcda lies somewhere under it, so without
+# an explicit search path the report would silently merge all five. Measured on
+# gcovr 8.6: with this search path, an empty directory yields an empty report
+# and the real one yields 177 files.
+objdir=$PWD/build/$1/threadx/CMakeFiles/threadx.dir/common/src
+
+# The Linux port's own sources are deliberately outside -f. gcno files exist for
+# two directories -- common/src and ports/linux/gnu/src -- and only the first is
+# reported. The kernel is what this suite is here to cover; the architecture
+# ports are validated functionally rather than structurally, and linux/gnu is a
+# development host port that nothing ships on. Written down because a filter
+# argument on its own is not a decision the next reader can see.
+
+# Per-configuration output is kept in a subdirectory of its own, and the merged
+# report sits alongside it at the top. That is not tidiness: the Pages deploy
+# uploads coverage_report wholesale and merges the ThreadX and SMP artifacts
+# into one tree, and every configuration directory has the same name in both
+# suites. Left at the top level, default_build_coverage/ from one suite would
+# overwrite the other's on the published site. Nested here, the top level still
+# holds exactly the one suite directory the deploy expects.
+mkdir -p coverage_report/per_configuration/$1
+gcovr --gcov-executable "$GCOV" -r "$repo_root" -f "$filter" "$objdir" \
+      --json coverage_report/per_configuration/$1.json \
+      --xml-pretty --output coverage_report/per_configuration/$1.xml
+gcovr --gcov-executable "$GCOV" -r "$repo_root" -f "$filter" "$objdir" --html --html-details --output coverage_report/per_configuration/$1/index.html
+
+# An empty report is not an error as far as gcovr is concerned: it warns and
+# exits 0. Worse, it advertises line-rate="1.0" alongside lines-valid="0", so
+# every downstream consumer reads "no data at all" as "100% covered". A coverage
+# threshold cannot catch that, because an empty report passes any threshold. So
+# the assertion belongs here, next to the paths that would cause it.
+if ! grep -q "<class " coverage_report/per_configuration/$1.xml; then
+    echo "coverage.sh: the report for '$1' contains no files." >&2
+    echo "Expected gcda files under $objdir." >&2
+    exit 1
+fi