compiler: separate package exports from entry roots

cmd/w6c/gc.h

@@ -52,13 +52,12 @@ struct Cg {
 				 * Off on the combined path (every existing
 				 * invocation) so M3 is a pure addition. */
 	int	sep_isdep;	/* #99: this unit is a sep DEPENDENCY, not the
-				 * root/link-entry unit. Set from `wwiout != NULL`
-				 * in main: the producer passes -I (.wwi output)
-				 * to DEP units only — the root's .wwi is stripped
-				 * (#69), so wwiout==NULL <=> root/link-entry unit.
-				 * Gates the bare-`main` carve-out: a dep's `fn
-				 * main` must mangle on its path like any decl;
-				 * only the root entry stays bare. */
+				 * root/link-entry unit. The compiler's explicit
+				 * --entry flag clears this independently of -I:
+				 * every package action may emit export data. Gates
+				 * the bare-`main` carve-out: a dep's `fn main` must
+				 * mangle on its path like any decl; only the root
+				 * entry stays bare. */
 };
 
 /* cgen.c */