From 9eb4ee69fee3e117f40cb9e40cc3fac846afbee2 Mon Sep 17 00:00:00 2001
From: James <85808999+TheGreatSageEqualToHeaven@users.noreply.github.com>
Date: Tue, 18 Mar 2025 18:22:19 +0000
Subject: [PATCH] Add cmake setting to build as dll

---
 CMakeLists.txt | 49 +++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 39 insertions(+), 10 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5286fd9f..08cf6fd8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -12,6 +12,8 @@ option(LUAU_BUILD_WEB "Build Web module" OFF)
 option(LUAU_WERROR "Warnings as errors" OFF)
 option(LUAU_STATIC_CRT "Link with the static CRT (/MT)" OFF)
 option(LUAU_EXTERN_C "Use extern C for all APIs" OFF)
+option(LUAU_EXPORT_DLL "Exports to DLL" OFF)
+
 
 cmake_policy(SET CMP0054 NEW)
 cmake_policy(SET CMP0091 NEW)
@@ -25,13 +27,24 @@ project(Luau LANGUAGES CXX C)
 add_library(Luau.Common INTERFACE)
 add_library(Luau.CLI.lib STATIC)
 add_library(Luau.Ast STATIC)
-add_library(Luau.Compiler STATIC)
-add_library(Luau.Config STATIC)
-add_library(Luau.Analysis STATIC)
-add_library(Luau.EqSat STATIC)
-add_library(Luau.CodeGen STATIC)
-add_library(Luau.VM STATIC)
-add_library(isocline STATIC)
+
+if(LUAU_EXPORT_DLL)
+    add_library(Luau.Compiler SHARED)
+    add_library(Luau.Config SHARED)
+    add_library(Luau.Analysis SHARED)
+    add_library(Luau.EqSat SHARED)
+    add_library(Luau.CodeGen SHARED)
+    add_library(Luau.VM SHARED)
+    add_library(isocline SHARED)
+else()
+    add_library(Luau.Compiler STATIC)
+    add_library(Luau.Config STATIC)
+    add_library(Luau.Analysis STATIC)
+    add_library(Luau.EqSat STATIC)
+    add_library(Luau.CodeGen STATIC)
+    add_library(Luau.VM STATIC)
+    add_library(isocline STATIC)
+endif()
 
 if(LUAU_BUILD_CLI)
     add_executable(Luau.Repl.CLI)
@@ -161,9 +174,25 @@ if(LUAU_EXTERN_C)
     # enable extern "C" for VM (lua.h, lualib.h) and Compiler (luacode.h) to make Luau friendlier to use from non-C++ languages
     # note that we enable LUA_USE_LONGJMP=1 as well; otherwise functions like luaL_error will throw C++ exceptions, which can't be done from extern "C" functions
     target_compile_definitions(Luau.VM PUBLIC LUA_USE_LONGJMP=1)
-    target_compile_definitions(Luau.VM PUBLIC LUA_API=extern\"C\")
-    target_compile_definitions(Luau.Compiler PUBLIC LUACODE_API=extern\"C\")
-    target_compile_definitions(Luau.CodeGen PUBLIC LUACODEGEN_API=extern\"C\")
+
+    if(LUAU_EXPORT_DLL)
+        if(MSVC)
+            target_compile_definitions(Luau.VM PUBLIC "LUA_API=extern \"C\" __declspec(dllexport)")
+            target_compile_definitions(Luau.Compiler PUBLIC "LUACODE_API=extern \"C\" __declspec(dllexport)")
+            target_compile_definitions(Luau.CodeGen PUBLIC "LUACODEGEN_API=extern \"C\" __declspec(dllexport)")
+        else()
+            # GCC/Clang
+            target_compile_definitions(Luau.VM PUBLIC "LUA_API=extern \"C\" __attribute__((visibility(\"default\")))")
+            target_compile_definitions(Luau.Compiler PUBLIC "LUACODE_API=extern \"C\" __attribute__((visibility(\"default\")))")
+            target_compile_definitions(Luau.CodeGen PUBLIC "LUACODEGEN_API=extern \"C\" __attribute__((visibility(\"default\")))")
+        endif()
+    else()
+        # For static builds (or if not exporting) just use extern "C"
+        target_compile_definitions(Luau.VM PUBLIC "LUA_API=extern \"C\"")
+        target_compile_definitions(Luau.Compiler PUBLIC "LUACODE_API=extern \"C\"")
+        target_compile_definitions(Luau.CodeGen PUBLIC "LUACODEGEN_API=extern \"C\"")
+    endif()
+
 endif()
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC" AND MSVC_VERSION GREATER_EQUAL 1924)