Add new cmake setting

Co-Authored-By: Yumacide <88495241+Yumacide@users.noreply.github.com>

CMakeLists.txt

@@ -6,12 +6,13 @@ endif()
 
 cmake_minimum_required(VERSION 3.0)
 
-option(LUAU_BUILD_CLI "Build CLI" ON)
+option(LUAU_BUILD_CLI "Build CLI" OFF)
-option(LUAU_BUILD_TESTS "Build tests" ON)
+option(LUAU_BUILD_TESTS "Build tests" OFF)
 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_EXTERN_C "Use extern C for all APIs" ON)
+option(LUAU_EXPORT_DLL "Exports to DLL with C linkage" ON)
 option(LUAU_NATIVE "Enable support for native code generation" OFF)
 
 if(LUAU_STATIC_CRT)
@@ -23,11 +24,20 @@ endif()
 project(Luau LANGUAGES CXX C)
 add_library(Luau.Common INTERFACE)
 add_library(Luau.Ast STATIC)
-add_library(Luau.Compiler STATIC)
+
-add_library(Luau.Analysis STATIC)
+if(LUAU_EXPORT_DLL)
-add_library(Luau.CodeGen STATIC)
+    add_library(Luau.Compiler SHARED)
-add_library(Luau.VM STATIC)
+    add_library(Luau.Analysis SHARED)
-add_library(isocline STATIC)
+    add_library(Luau.CodeGen SHARED)
+    add_library(Luau.VM SHARED)
+    add_library(isocline SHARED)
+else()
+    add_library(Luau.Compiler STATIC)
+    add_library(Luau.Analysis 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)
@@ -128,9 +138,20 @@ target_compile_options(isocline PRIVATE ${LUAU_OPTIONS} ${ISOCLINE_OPTIONS})
 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
+    # LUAU_EXPORT_DLL exists to make Luau useable from non-C++ languages properly that cant rely on `extern`
     target_compile_definitions(Luau.VM PUBLIC LUA_USE_LONGJMP=1)
-    target_compile_definitions(Luau.VM PUBLIC LUA_API=extern\"C\")
+    if(LUAU_EXPORT_DLL)
-    target_compile_definitions(Luau.Compiler PUBLIC LUACODE_API=extern\"C\")
+        target_compile_definitions(Luau.VM PUBLIC LUA_API_C_EXPORT)
+        target_compile_definitions(Luau.Compiler PUBLIC LUACOPDE_API_C_EXPORT)
+    else()
+        target_compile_definitions(Luau.VM PUBLIC LUA_API=extern\"C\")
+        target_compile_definitions(Luau.Compiler PUBLIC LUACODE_API=extern\"C\")
+    endif()
+else()
+    if(LUAU_EXPORT_DLL) 
+        target_compile_definitions(Luau.VM PUBLIC LUA_API_EXPORT)
+        target_compile_definitions(Luau.Compiler PUBLIC LUACOPDE_API_EXPORT)
+    endif()
 endif()
 
 if(LUAU_NATIVE)

Compiler/include/luacode.h

@@ -3,6 +3,15 @@
 
 #include <stddef.h>
 
+// Can be used to export public APIs to DLL
+#ifdef LUA_API_C_EXPORT 
+#define LUACODE_API extern "C" __declspec(dllexport)
+#endif 
+
+#ifdef LUA_API_EXPORT
+#define LUACODE_API extern __declspec(dllexport)
+#endif 
+
 // Can be used to reconfigure visibility/exports for public APIs
 #ifndef LUACODE_API
 #define LUACODE_API extern

VM/include/luaconf.h

@@ -33,6 +33,15 @@
 #define LUA_NORETURN __attribute__((__noreturn__))
 #endif
 
+// Can be used to export public APIs to DLL
+#ifdef LUA_API_C_EXPORT 
+#define LUA_API extern "C" __declspec(dllexport)
+#endif 
+
+#ifdef LUA_API_EXPORT
+#define LUA_API extern __declspec(dllexport)
+#endif 
+
 // Can be used to reconfigure visibility/exports for public APIs
 #ifndef LUA_API
 #define LUA_API extern