From c73c88033d42158a798c97c6bf3114d28e02e62b Mon Sep 17 00:00:00 2001
From: "Emil J. Tywoniak" <emil@tywoniak.eu>
Date: Tue, 15 Oct 2024 12:00:51 +0200
Subject: [PATCH] hashlib: only include in one place

---
 kernel/hashlib.h      | 2 ++
 kernel/yosys_common.h | 3 +--
 passes/cmds/rename.cc | 1 -
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/hashlib.h b/kernel/hashlib.h
index 2e4c49176..b4d82f80a 100644
--- a/kernel/hashlib.h
+++ b/kernel/hashlib.h
@@ -34,6 +34,8 @@ namespace hashlib {
  * Hashlib doesn't know how to hash silly Yosys-specific types.
  * Hashlib doesn't depend on Yosys and can be used standalone.
  * Please don't use hashlib standalone for new projects.
+ * Never directly include kernel/hashlib.h in Yosys code.
+ * Instead include kernel/yosys_common.h
  *
  * The hash_ops type is now always left to its default value, derived
  * from templated functions through SFINAE. Providing custom ops is
diff --git a/kernel/yosys_common.h b/kernel/yosys_common.h
index 52f7f5f96..9370de330 100644
--- a/kernel/yosys_common.h
+++ b/kernel/yosys_common.h
@@ -134,8 +134,7 @@ YOSYS_NAMESPACE_BEGIN
 // Note: All headers included in hashlib.h must be included
 // outside of YOSYS_NAMESPACE before this or bad things will happen.
 #ifdef HASHLIB_H
-#  undef HASHLIB_H
-#  include "kernel/hashlib.h"
+#  error You've probably included hashlib.h under two namespace paths. Bad idea.
 #else
 #  include "kernel/hashlib.h"
 #  undef HASHLIB_H
diff --git a/passes/cmds/rename.cc b/passes/cmds/rename.cc
index 3f8d807b3..fe8b4a444 100644
--- a/passes/cmds/rename.cc
+++ b/passes/cmds/rename.cc
@@ -20,7 +20,6 @@
 #include "kernel/register.h"
 #include "kernel/rtlil.h"
 #include "kernel/log.h"
-#include "kernel/hashlib.h"
 
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN