[master] 00df3c9e3 vcc: record if any SUB references have been encountered

[Nils Goroll]

commit 00df3c9e380773f97d512ef2472e1bce5f69c944
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Sat Feb 6 14:25:12 2021 +0100

    vcc: record if any SUB references have been encountered
    
    For follow up commits, we will need to know if a VCL contains any
    references to the SUB type, that is, if the SUB type was used as a vmod
    function or method argument.

diff --git a/lib/libvcc/vcc_compile.c b/lib/libvcc/vcc_compile.c
index d4dfa0601..78457763d 100644
--- a/lib/libvcc/vcc_compile.c
+++ b/lib/libvcc/vcc_compile.c
@@ -538,7 +538,7 @@ EmitStruct(const struct vcc *tl)
 	Fc(tl, 0, "\t.ref = VGC_ref,\n");
 	Fc(tl, 0, "\t.nref = VGC_NREFS,\n");
 	Fc(tl, 0, "\t.nsrc = VGC_NSRCS,\n");
-	Fc(tl, 0, "\t.nsub = %d,\n", tl->nsub);
+	Fc(tl, 0, "\t.nsub = %d,\n", tl->subref > 0 ? tl->nsub : 0);
 	Fc(tl, 0, "\t.srcname = srcname,\n");
 	Fc(tl, 0, "\t.srcbody = srcbody,\n");
 	Fc(tl, 0, "\t.nvmod = %u,\n", tl->vmod_count);
diff --git a/lib/libvcc/vcc_compile.h b/lib/libvcc/vcc_compile.h
index 814414c66..2dff6dfa5 100644
--- a/lib/libvcc/vcc_compile.h
+++ b/lib/libvcc/vcc_compile.h
@@ -267,6 +267,7 @@ struct vcc {
 	struct vsb		*sb;
 	int			err;
 	unsigned		nsub;
+	unsigned		subref;	// SUB arguments present
 	struct proc		*curproc;
 	VTAILQ_HEAD(, proc)	procs;
 
diff --git a/lib/libvcc/vcc_expr.c b/lib/libvcc/vcc_expr.c
index 06d2c7d75..f44a868ab 100644
--- a/lib/libvcc/vcc_expr.c
+++ b/lib/libvcc/vcc_expr.c
@@ -446,6 +446,8 @@ vcc_do_arg(struct vcc *tl, struct func_arg *fa)
 		vcc_do_enum(tl, fa, PF(tl->t));
 		SkipToken(tl, ID);
 	} else {
+		if (fa->type == SUB)
+			tl->subref++;
 		vcc_expr0(tl, &e2, fa->type);
 		ERRCHK(tl);
 		assert(e2->fmt == fa->type);