From cec426a0781c0cca148cedf46117fd90277303d0 Mon Sep 17 00:00:00 2001
From: Daniel Krebs <github@daniel-krebs.net>
Date: Tue, 11 Apr 2017 13:21:39 +0200
Subject: [PATCH] cmake: add intermediate target hermit-bootstrap to build with
 bootstrap compiler

---
 .gitignore                                    |  1 +
 CMakeLists.txt                                | 40 +++++++++++++++----
 .../HermitCore-Toolchain-x86-bootstrap.cmake  |  4 +-
 cmake/HermitCore.cmake                        |  6 ++-
 include/hermit/CMakeLists.txt                 |  7 ++++
 5 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/.gitignore b/.gitignore
index fabe22240..841e46c24 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,3 +10,4 @@
 **/build/*
 .idea/*
 qemu-vlan0.pcap
+cmake/cmake-3.7.2-Linux-x86_64/*
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e69e14459..970a1c753 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,21 +58,23 @@ list(APPEND KERNEL_OBJECTS
 	$<TARGET_OBJECTS:${X86_KERNEL_C_TARGET}>)
 
 # finally build libhermit.a
-add_library(hermit STATIC ${KERNEL_OBJECTS})
+add_library(hermit-bootstrap STATIC ${KERNEL_OBJECTS})
+set_target_properties(hermit-bootstrap PROPERTIES
+	ARCHIVE_OUTPUT_NAME hermit)
 
 # after compiling ASM sources, we need to post-process them. Adding this
 # dependency makes sure that this is done before hermit is linked
-add_dependencies(hermit ${X86_KERNEL_TARGET})
+add_dependencies(hermit-bootstrap ${X86_KERNEL_TARGET})
 
 add_custom_command(
 	TARGET
-		hermit POST_BUILD
+		hermit-bootstrap POST_BUILD
 	# rename sections in final library
 	COMMAND
 		${CMAKE_OBJCOPY} --rename-section .bss=.kbss
 						 --rename-section .text=.ktext
 						 --rename-section .data=.kdata
-						 $<TARGET_FILE:hermit>
+						 $<TARGET_FILE:hermit-bootstrap>
 
 	# copy libhermit.a into local prefix directory so that all subsequent
 	# targets can link against the freshly built version (as opposed to
@@ -81,7 +83,7 @@ add_custom_command(
 		${CMAKE_COMMAND} -E make_directory ${LOCAL_PREFIX_ARCH_LIB_DIR}
 	COMMAND
 		${CMAKE_COMMAND} -E copy_if_different
-							$<TARGET_FILE:hermit>
+							$<TARGET_FILE:hermit-bootstrap>
 							${LOCAL_PREFIX_ARCH_LIB_DIR}/
 
 	# and also copy headers into local prefix
@@ -96,11 +98,33 @@ add_custom_command(
 							${CMAKE_BINARY_DIR}/include/hermit/*.asm
 							${LOCAL_PREFIX_ARCH_INCLUDE_DIR}/hermit/)
 
+
 # deploy libhermit.a and headers for package creation
-install(TARGETS hermit
-	DESTINATION ${TARGET_ARCH}/lib)
+install(TARGETS hermit-bootstrap
+	DESTINATION ${TARGET_ARCH}/lib
+	COMPONENT bootstrap)
+
 install(DIRECTORY include/hermit
-	DESTINATION ${TARGET_ARCH}/include/)
+	DESTINATION ${TARGET_ARCH}/include/
+	COMPONENT bootstrap
+	FILES_MATCHING
+		PATTERN *.h)
+
+# provide custom target to only install libhermit without its runtimes which is
+# needed during the compilation of the cross toolchain
+add_custom_target(hermit-bootstrap-install
+	DEPENDS
+		hermit-bootstrap
+	COMMAND
+		${CMAKE_COMMAND}
+			-DCMAKE_INSTALL_COMPONENT=bootstrap
+			-DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
+			-P cmake_install.cmake)
+
+# The target 'hermit' includes the HermitCore kernel and several runtimes.
+# Applications should depend on this target if they link against HermitCore.
+add_custom_target(hermit
+	DEPENDS hermit-bootstrap)
 
 
 ### External projects
diff --git a/cmake/HermitCore-Toolchain-x86-bootstrap.cmake b/cmake/HermitCore-Toolchain-x86-bootstrap.cmake
index aa83a3900..4471196e2 100644
--- a/cmake/HermitCore-Toolchain-x86-bootstrap.cmake
+++ b/cmake/HermitCore-Toolchain-x86-bootstrap.cmake
@@ -4,8 +4,6 @@ include_guard()
 set(CMAKE_C_COMPILER_WORKS 1 CACHE INTERNAL "")
 set(CMAKE_CXX_COMPILER_WORKS 1 CACHE INTERNAL "")
 
-# unset unneeded compilers
+# bootstrap toolchain cannot compile neither Go nor Fortran
 unset(CMAKE_Go_COMPILER)
 unset(CMAKE_Fortran_COMPILER)
-
-set(BOOTSTRAP true)
diff --git a/cmake/HermitCore.cmake b/cmake/HermitCore.cmake
index e5134f44b..4d6ac9d00 100644
--- a/cmake/HermitCore.cmake
+++ b/cmake/HermitCore.cmake
@@ -27,7 +27,11 @@ endif()
 
 # use default toolchain if not specified by user
 if(NOT CMAKE_TOOLCHAIN_FILE)
-	set(CMAKE_TOOLCHAIN_FILE ${CMAKE_CURRENT_LIST_DIR}/HermitCore-Toolchain-${HERMIT_ARCH}.cmake)
+	if(BOOTSTRAP)
+		# use bootstrap toolchain if requested
+		set(_BOOTSTRAP_ARCH_SUFFIX -bootstrap)
+	endif()
+	set(CMAKE_TOOLCHAIN_FILE ${CMAKE_CURRENT_LIST_DIR}/HermitCore-Toolchain-${HERMIT_ARCH}${_BOOTSTRAP_ARCH_SUFFIX}.cmake)
 endif()
 
 # NASM detection will change binary format depending on host system, but
diff --git a/include/hermit/CMakeLists.txt b/include/hermit/CMakeLists.txt
index 921ca40f1..5f4dee9b4 100644
--- a/include/hermit/CMakeLists.txt
+++ b/include/hermit/CMakeLists.txt
@@ -6,3 +6,10 @@ configure_file(config.asm.in config.asm)
 # Show include files in IDE
 file(GLOB_RECURSE HERMIT_INCLUDES "*")
 add_custom_target(hermit_includes_ide SOURCES ${HERMIT_INCLUDES})
+
+# install generated config files when building libhermit for bootstrapping
+install(FILES
+	${GENERATED_CONFIG_DIR}/hermit/config.h
+	${GENERATED_CONFIG_DIR}/hermit/config.asm
+	DESTINATION ${TARGET_ARCH}/include/hermit/
+	COMPONENT bootstrap)