build: reject empty BUILDKIT_SYNTAX overrides

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>
2026-03-24 15:35:08 +01:00
parent 771e0de740
commit 7c44ec11ec
2 changed files with 14 additions and 1 deletions
@@ -298,7 +298,11 @@ func toSolveOpt(ctx context.Context, np *noderesolver.ResolvedNode, multiDriver
 	}

 	if v, ok := opt.BuildArgs["BUILDKIT_SYNTAX"]; ok {
-		p := strings.SplitN(strings.TrimSpace(v), " ", 2)
+		cmdline := strings.TrimSpace(v)
+		if cmdline == "" {
+			return nil, nil, errors.Errorf("empty BUILDKIT_SYNTAX build-arg is invalid, use --build-arg BUILDKIT_SYNTAX without '=' for optional behavior")
+		}
+		p := strings.SplitN(cmdline, " ", 2)
 		so.Frontend = "gateway.v0"
 		so.FrontendAttrs["source"] = p[0]
 		so.FrontendAttrs["cmdline"] = v