ability to build stage1 using only a zig tarball

The main idea here is that there are now 2 ways to get a stage1 zig
binary:

 * The cmake path. Requirements: cmake, system C++ compiler, system
   LLVM, LLD, Clang libraries, compiled by the system C++ compiler.

 * The zig path. Requirements: a zig installation, system LLVM, LLD,
   Clang libraries, compiled by the zig installation.

Note that the former can be used to now take the latter path.

Removed config.h.in and config.zig.in. The build.zig script no longer is
coupled to the cmake script.

cmake no longer tries to determine the zig version. A build with cmake
will yield a stage1 zig binary that reports 0.0.0+zig0. This is going to
get reverted.

`zig build` now accepts `-Dstage1` which will build the stage1 compiler,
and put the stage2 backend behind a feature flag.

build.zig is simplified to only support the use case of enabling LLVM
support when the LLVM, LLD, and Clang libraries were built by zig. This
part is probably sadly going to have to get reverted to make package
maintainers happy.

Zig build system addBuildOption supports a couple new types.

The biggest reason to make this change is that the zig path is an
attractive option for doing compiler development work on Windows. It
allows people to work on the compiler without having MSVC installed,
using only a .zip file that contains Zig + LLVM/LLD/Clang libraries.

1 files changed, 8 insertions, 45 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ad38cdb18b..b9a81575be 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,34 +24,6 @@ set(CMAKE_USER_MAKE_RULES_OVERRIDE_CXX
 project(zig C CXX)
 set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
 
-set(ZIG_VERSION_MAJOR 0)
-set(ZIG_VERSION_MINOR 7)
-set(ZIG_VERSION_PATCH 0)
-set(ZIG_VERSION "" CACHE STRING "Override Zig version string. Default is to find out with git.")
-
-if("${ZIG_VERSION}" STREQUAL "")
-    set(ZIG_VERSION "${ZIG_VERSION_MAJOR}.${ZIG_VERSION_MINOR}.${ZIG_VERSION_PATCH}")
-    find_program(GIT_EXE NAMES git)
-    if(GIT_EXE)
-        execute_process(
-            COMMAND ${GIT_EXE} -C ${CMAKE_SOURCE_DIR} name-rev HEAD --tags --name-only --no-undefined --always
-            RESULT_VARIABLE EXIT_STATUS
-            OUTPUT_VARIABLE ZIG_GIT_REV
-            OUTPUT_STRIP_TRAILING_WHITESPACE
-            ERROR_QUIET)
-        if(EXIT_STATUS EQUAL "0")
-            if(ZIG_GIT_REV MATCHES "\\^0$")
-                if(NOT("${ZIG_GIT_REV}" STREQUAL "${ZIG_VERSION}^0"))
-                    message("WARNING: Tag does not match configured Zig version")
-                endif()
-            else()
-                set(ZIG_VERSION "${ZIG_VERSION}+${ZIG_GIT_REV}")
-            endif()
-        endif()
-    endif()
-endif()
-message("Configuring zig version ${ZIG_VERSION}")
-
 set(ZIG_STATIC off CACHE BOOL "Attempt to build a static zig executable (not compatible with glibc)")
 set(ZIG_STATIC_LLVM off CACHE BOOL "Prefer linking against static LLVM libraries")
 set(ZIG_PREFER_CLANG_CPP_DYLIB off CACHE BOOL "Try to link against -lclang-cpp")
@@ -63,9 +35,6 @@ endif()
 
 if(ZIG_STATIC)
     set(ZIG_STATIC_LLVM "on")
-    set(ZIG_LINK_MODE "Static")
-else()
-    set(ZIG_LINK_MODE "Dynamic")
 endif()
 
 string(REGEX REPLACE "\\\\" "\\\\\\\\" ZIG_LIBC_LIB_DIR_ESCAPED "${ZIG_LIBC_LIB_DIR}")
@@ -264,8 +233,6 @@ set(LIBC_FILES_DEST "${ZIG_LIB_DIR}/libc")
 set(LIBUNWIND_FILES_DEST "${ZIG_LIB_DIR}/libunwind")
 set(LIBCXX_FILES_DEST "${ZIG_LIB_DIR}/libcxx")
 set(ZIG_STD_DEST "${ZIG_LIB_DIR}/std")
-set(ZIG_CONFIG_H_OUT "${CMAKE_BINARY_DIR}/config.h")
-set(ZIG_CONFIG_ZIG_OUT "${CMAKE_BINARY_DIR}/config.zig")
 
 # This is our shim which will be replaced by stage1.zig.
 set(ZIG0_SOURCES
@@ -313,7 +280,6 @@ set(ZIG_CPP_SOURCES
 # then manually running the build-obj command (see BUILD_ZIG1_ARGS), and then looking
 # in the zig-cache directory for the compiler-generated list of zig file dependencies.
 set(ZIG_STAGE2_SOURCES
-    "${ZIG_CONFIG_ZIG_OUT}"
     "${CMAKE_SOURCE_DIR}/lib/std/array_hash_map.zig"
     "${CMAKE_SOURCE_DIR}/lib/std/array_list.zig"
     "${CMAKE_SOURCE_DIR}/lib/std/ascii.zig"
@@ -553,6 +519,7 @@ set(ZIG_STAGE2_SOURCES
     "${CMAKE_SOURCE_DIR}/src/print_env.zig"
     "${CMAKE_SOURCE_DIR}/src/print_targets.zig"
     "${CMAKE_SOURCE_DIR}/src/stage1.zig"
+    "${CMAKE_SOURCE_DIR}/src/stage1_config.zig"
     "${CMAKE_SOURCE_DIR}/src/target.zig"
     "${CMAKE_SOURCE_DIR}/src/tracy.zig"
     "${CMAKE_SOURCE_DIR}/src/translate_c.zig"
@@ -571,15 +538,6 @@ if(MSVC)
     endif()
 endif()
 
-configure_file (
-    "${CMAKE_SOURCE_DIR}/src/stage1/config.h.in"
-    "${ZIG_CONFIG_H_OUT}"
-)
-configure_file (
-    "${CMAKE_SOURCE_DIR}/src/config.zig.in"
-    "${ZIG_CONFIG_ZIG_OUT}"
-)
-
 include_directories(
     ${CMAKE_SOURCE_DIR}
     ${CMAKE_BINARY_DIR}
@@ -594,6 +552,12 @@ else(MSVC)
   set(EXE_CFLAGS "-std=c++14")
 endif(MSVC)
 
+if(ZIG_STATIC)
+    set(EXE_CFLAGS "${EXE_CFLAGS} -DZIG_LINK_MODE=Static")
+else()
+    set(EXE_CFLAGS "${EXE_CFLAGS} -DZIG_LINK_MODE=Dynamic")
+endif()
+
 if("${CMAKE_BUILD_TYPE}" STREQUAL "Debug")
     if(MSVC)
         set(EXE_CFLAGS "${EXE_CFLAGS} /w")
@@ -720,7 +684,7 @@ set(BUILD_ZIG1_ARGS
     "-femit-bin=${ZIG1_OBJECT}"
     "${ZIG1_RELEASE_ARG}"
     -lc
-    --pkg-begin build_options "${ZIG_CONFIG_ZIG_OUT}"
+    --pkg-begin build_options "${CMAKE_SOURCE_DIR}/src/stage1_config.zig"
     --pkg-end
     --pkg-begin compiler_rt "${CMAKE_SOURCE_DIR}/lib/std/special/compiler_rt.zig"
     --pkg-end
@@ -769,7 +733,6 @@ set(ZIG_INSTALL_ARGS "build"
     --override-lib-dir "${CMAKE_SOURCE_DIR}/lib"
     "-Dlib-files-only"
     --prefix "${CMAKE_INSTALL_PREFIX}"
-    "-Dconfig_h=${ZIG_CONFIG_H_OUT}"
     install
 )