Author: Andy Green <andy@warmcat.com>
Date: Sun Oct 04 17:21:47 2026 +0100

scripts: sync-c-states: build h3 where gnutls is installed

C measures its state table's coverage with h3 in its builds, and some
rows only h3 reaches, the client's quic to tcp fallback among them.  The
sync built without h3 always, since h3 needs gnutls, so those rows could
never fire in it however the host was set up.  Build h3 where gnutls is
there, as C does, and say so where it is not.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019kg5Eemy68ZaqDBcUJQG6J


diff --git a/scripts/sync-c-states.sh b/scripts/sync-c-states.sh
index 8e6c853..1a1b6d9 100755
--- a/scripts/sync-c-states.sh
+++ b/scripts/sync-c-states.sh
@@ -20,8 +20,9 @@
 # The suite runs in the three builds C's README measures coverage over: the
 # default, one adding the options some rows need, and one with tls accepts
 # on a worker.  Each has LWS_WITH_STATE_TRACE and LWS_WITH_STATE_CHECK, so
-# the suite also aborts on any edge the table does not allow.  h3 is left
-# out, since it needs gnutls.
+# the suite also aborts on any edge the table does not allow.  h3 is built
+# where gnutls is installed, as C's own measurement is; without it the rows
+# only h3 reaches (quic to tcp among them) are never fired.
 #
 # The builds go to <build dir>-<name>, by default <checkout>/build-npro-
 # states-<name>; they are reconfigured each time.  C's ctest-background.sh
@@ -55,6 +56,13 @@ if ! command -v netstat >/dev/null 2>&1 && ! command -v ss >/dev/null 2>&1; then
 	exit 1
 fi
 
+if pkg-config --exists gnutls 2>/dev/null; then
+	h3=ON
+else
+	h3=OFF
+	echo "no gnutls: building without h3, so its rows will not fire" >&2
+fi
+
 raw="$(mktemp)"
 trap 'rm -f "$raw"' EXIT
 
@@ -65,7 +73,7 @@ suite() {
 	echo "== C build: $name"
 	cmake -S "$c" -B "$b-$name" -DCMAKE_BUILD_TYPE=DEBUG \
 		-DLWS_WITH_STATE_TRACE=ON -DLWS_WITH_STATE_CHECK=ON \
-		-DLWS_WITH_HTTP3=OFF -DLWS_WITH_MINIMAL_EXAMPLES=ON \
+		-DLWS_WITH_HTTP3="$h3" -DLWS_WITH_MINIMAL_EXAMPLES=ON \
 		-DLWS_WITHOUT_EXTENSIONS=OFF -DLWS_WITH_ZLIB=ON "$@"
 	cmake --build "$b-$name" -j "$jobs"
 	# shellcheck disable=SC2086