From ad139b7118474fdecf1afb4c2684929ce417f167 Mon Sep 17 00:00:00 2001
From: Miodrag Milanovic <mmicko@gmail.com>
Date: Thu, 18 Jun 2026 12:57:10 +0200
Subject: [PATCH] Add option to build without slang

---
 CMakeLists.txt                 | 2 ++
 frontends/slang/CMakeLists.txt | 4 +++-
 libs/CMakeLists.txt            | 6 ++++--
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a37b52ebe..dad7277f7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,6 +53,7 @@ option(YOSYS_WITHOUT_ZLIB "Disable zlib integration" OFF)
 option(YOSYS_WITHOUT_LIBFFI "Disable libffi integration" OFF)
 option(YOSYS_WITHOUT_READLINE "Disable readline integration" OFF)
 option(YOSYS_WITHOUT_EDITLINE "Disable editline integration" OFF)
+option(YOSYS_WITHOUT_SLANG "Disable Slang integration" OFF)
 option(YOSYS_WITHOUT_TCL "Disable Tcl integration" OFF)
 option(YOSYS_WITH_PYTHON "Enable Python integration" OFF)
 
@@ -308,6 +309,7 @@ condition(YOSYS_ENABLE_EDITLINE editline_FOUND AND NOT YOSYS_WITHOUT_EDITLINE AN
 condition(YOSYS_ENABLE_TCL tcl_FOUND AND libtommath_FOUND AND NOT YOSYS_WITHOUT_TCL)
 condition(YOSYS_ENABLE_PYTHON Python3Devel_FOUND AND PyosysEnv_FOUND AND YOSYS_WITH_PYTHON)
 condition(YOSYS_ENABLE_VERIFIC YOSYS_VERIFIC_DIR AND zlib_FOUND)
+condition(YOSYS_ENABLE_SLANG NOT YOSYS_WITHOUT_SLANG)
 
 # Describe dependencies and features
 # CMake 4.0 would let us use proper conditions, but that's too new for now.
diff --git a/frontends/slang/CMakeLists.txt b/frontends/slang/CMakeLists.txt
index da50e2494..850b8d26f 100644
--- a/frontends/slang/CMakeLists.txt
+++ b/frontends/slang/CMakeLists.txt
@@ -26,10 +26,12 @@ yosys_frontend(slang
 	lib/src/variables.cc
 	lib/src/variables.h
 	${CMAKE_CURRENT_BINARY_DIR}/version.h
+	ENABLE_IF
+		YOSYS_ENABLE_SLANG
 	INCLUDE_DIRS
 		${CMAKE_CURRENT_BINARY_DIR}
 	LIBRARIES
-		slang::slang
+		$<${YOSYS_ENABLE_SLANG}:slang::slang>
 		fmt::fmt
 )
 
diff --git a/libs/CMakeLists.txt b/libs/CMakeLists.txt
index 6e09fbc3e..126635687 100644
--- a/libs/CMakeLists.txt
+++ b/libs/CMakeLists.txt
@@ -17,6 +17,8 @@ FetchContent_Declare(
     SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/fmt
 )
 FetchContent_MakeAvailable(fmt)
-set(SLANG_USE_MIMALLOC OFF)
-add_subdirectory(slang)
+if (NOT YOSYS_WITHOUT_SLANG)
+    set(SLANG_USE_MIMALLOC OFF)
+    add_subdirectory(slang)
+endif()
 set(BUILD_SHARED_LIBS "${_old_BUILD_SHARED_LIBS}")