From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 5 Jan 2023 09:36:41 +0000 (+0200)
Subject: Avoid spurious dependency loop errors from side effects
X-Git-Url: http://git.tdb.fi/?p=builder.git;a=commitdiff_plain;h=b0438fd2d85d6937b67db38c6138b0783962d8b2

Avoid spurious dependency loop errors from side effects

If the primary target depends on its own side effect (such as a generated
source file including a header generated by the same command), this could
cause the side effect's prepare() to be entered recursively.
---

diff --git a/source/lib/target.cpp b/source/lib/target.cpp
index f99b0bc..d1aaf73 100644
--- a/source/lib/target.cpp
+++ b/source/lib/target.cpp
@@ -111,6 +111,9 @@ void Target::mark_rebuild(const string &reason)
 
 void Target::prepare()
 {
+	if(primary_target && primary_target->state<PREPARING)
+		primary_target->prepare();
+
 	if(state>PREPARING)
 		return;
 	if(state==PREPARING)
@@ -122,8 +125,6 @@ void Target::prepare()
 	}
 
 	state = PREPARING;
-	if(primary_target)
-		primary_target->prepare();
 	/* Prepare existing dependencies early, because their information may be
 	needed to find other dependencies. */
 	for(Target *d: depends)