From 1bf29a0ae1fffee8a009dfbc8da2d7c048f6eb20 Mon Sep 17 00:00:00 2001
From: Enan Ajmain <3nan.ajmain@gmail.com>
Date: Sun, 7 May 2023 04:47:45 +0600
Subject: [PATCH] build: add system lua include dir for lpeg

Problem: Lpeg requires Lua headers.  Currently the include directories
for Lpeg are set only to the bundled deps folder, so if the user wants
to use system Lua/Luajit, Lpeg will not find the system headers and will
fail to build.

Solution: Add system Lua/Luajit include directories when USE_BUNDLED_LUA
and USE_BUNDLED_LUAJIT are turned off.

Fixes #23469
---
 cmake.deps/cmake/BuildLpeg.cmake | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/cmake.deps/cmake/BuildLpeg.cmake b/cmake.deps/cmake/BuildLpeg.cmake
index 81efccf1f4..bbdc83d94d 100644
--- a/cmake.deps/cmake/BuildLpeg.cmake
+++ b/cmake.deps/cmake/BuildLpeg.cmake
@@ -1,4 +1,18 @@
-list(APPEND LPEG_CMAKE_ARGS "-DCMAKE_C_FLAGS:STRING=${DEPS_INCLUDE_FLAGS}")
+set(LPEG_INCLUDE_FLAGS ${DEPS_INCLUDE_FLAGS})
+
+if(NOT USE_BUNDLED_LUAJIT AND NOT USE_BUNDLED_LUA)
+  find_package(Luajit)
+  if(LUAJIT_FOUND)
+    string(CONCAT LPEG_INCLUDE_FLAGS ${DEPS_INCLUDE_FLAGS} " -I${LUAJIT_INCLUDE_DIR}")
+  else()
+    find_package(Lua 5.1 EXACT)
+    if(LUA_FOUND)
+      string(CONCAT LPEG_INCLUDE_FLAGS ${DEPS_INCLUDE_FLAGS} " -I${LUA_INCLUDE_DIR}")
+    endif()
+  endif()
+endif()
+
+list(APPEND LPEG_CMAKE_ARGS -DCMAKE_C_FLAGS=${LPEG_INCLUDE_FLAGS})
 
 ExternalProject_Add(lpeg
   URL ${LPEG_URL}