Description: Pass CFLAGS and CPPFLAGS to build process
 To enable hardening, CFLAGS and CPPFLAGS needs to be used in the build.
Author: Tobias Frost <tobi@debian.org>
Forwarded: https://github.com/minetest/minetest/pull/12799
Forwarded: https://github.com/minetest/irrlicht/pull/134
Last-Update: 2022-09-16 <YYYY-MM-DD, last update of the meta-information, optional>
---
This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -21,6 +21,8 @@
 	FORCE
 )
 
+set(CMAKE_C_FLAGS "${CMAKE_CFLAGS}  $ENV{CFLAGS} $ENV{CPPFLAGS}")
+
 
 # Set some random things default to not being visible in the GUI
 mark_as_advanced(EXECUTABLE_OUTPUT_PATH LIBRARY_OUTPUT_PATH)
@@ -584,6 +586,7 @@
 
 
 if(BUILD_SERVER)
+
 	add_executable(${PROJECT_NAME}server ${server_SRCS} ${extra_windows_SRCS})
 	add_dependencies(${PROJECT_NAME}server GenerateVersion)
 
@@ -757,7 +760,7 @@
 		endif()
 	endif()
 
-	set(CMAKE_CXX_FLAGS_RELEASE "-DNDEBUG ${RELEASE_WARNING_FLAGS} ${OTHER_FLAGS} -pipe -funroll-loops")
+	set(CMAKE_CXX_FLAGS_RELEASE "-DNDEBUG ${RELEASE_WARNING_FLAGS} ${OTHER_FLAGS} -pipe -funroll-loops $ENV{CPPFLAGS}")
 	if(CMAKE_SYSTEM_NAME MATCHES "(Darwin|BSD|DragonFly)")
 		set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Os")
 	else()
--- a/irrlicht/source/Irrlicht/CMakeLists.txt
+++ b/irrlicht/source/Irrlicht/CMakeLists.txt
@@ -14,8 +14,9 @@
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 if(CMAKE_CXX_COMPILER_ID MATCHES "^(GNU|Clang|AppleClang)$")
-	set(CMAKE_CXX_FLAGS_RELEASE "-O3")
-	set(CMAKE_CXX_FLAGS_DEBUG "-g")
+	set(CMAKE_CXX_FLAGS_RELEASE "-O3 $ENV{CPPFLAGS}")
+	set(CMAKE_CXX_FLAGS_DEBUG "-g $ENV{CPPFLAGS}")
+	set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELEASE} -g")
 
 	add_compile_options(-Wall -pipe -fno-exceptions -fno-rtti)