Generate build information from CHANGES.md
This PR significantly reworks the way glslang is versioned.
Instead of committing changes to the `GLSLANG_MINOR_VERSION` define in
`glslang/Public/ShaderLang.h`, and using `make-revision` to generate
`GLSLANG_PATCH_LEVEL` in `glslang/Include/revision.h`, all version
information is now derived from the new `CHANGES.md` file.
`CHANGES.md` acts as the single source of truth for glslang version
information, along with a convenient place to put all release notes for
each notable change made.
`CHANGES.md` is parsed using the new `build_info.py` python script.
This script can read basic template files to produce new source files,
which it does to read the new `build_info.h.tmpl` to generate (at build
time) a glslang private header at
`<build-dir>/include/glslang/build_info.h`.
I've written generators for each of the CMake, Bazel, gn, and
`Android.mk` build scripts.
The new version code conforms to the Semantic Versioning 2.0 spec.
This new version is also used by the CMake rules to produce versioned
shared objects, including a major-versioned SONAME.
New APIs:
---------
* `glslang::GetVersion()` returns a `Version` struct with the version
major, minor, patch and flavor.
Breaking API changes:
---------------------
* The public defines `GLSLANG_MINOR_VERSION` and `GLSLANG_PATCH_LEVEL`
have been entirely removed.
* `glslang/Public/ShaderLang.h` and `glslang/Include/revision.h` have
been deleted.
* Instead, `<build-dir>/include/glslang/build_info.h` is created in
the build directory, and `<build-dir>/include` is a CMake `PUBLIC`
(dependee-inherited) include directory for the glslang targets.
* `<build-dir>/include/glslang/build_info.h` contains the following
new #defines:
`GLSLANG_VERSION_MAJOR`, `GLSLANG_VERSION_MINOR`,
`GLSLANG_VERSION_PATCH`, `GLSLANG_VERSION_FLAVOR`,
`GLSLANG_VERSION_GREATER_THAN(major, minor, patch)`,
`GLSLANG_VERSION_GREATER_OR_EQUAL_TO(major, minor, patch)`,
`GLSLANG_VERSION_LESS_THAN(major, minor, patch)`,
`GLSLANG_VERSION_LESS_OR_EQUAL_TO(major, minor, patch)`
* The CMake install output directory contains a copy of
`build_info.h` at: `include/glslang/build_info.h`
* Python3 is now always required to build glslang (likely always
required for transitive dependency builds).
diff --git a/BUILD.gn b/BUILD.gn
index 4743753..09a0c71 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -46,6 +46,29 @@
_configs_to_add = [ "//build/config/compiler:no_chromium_code" ]
}
+action("glslang_build_info") {
+ script = "build_info.py"
+
+ src_dir = "."
+ changes_file = "CHANGES.md"
+ template_file = "build_info.h.tmpl"
+ out_file = "${target_gen_dir}/include/glslang/build_info.h"
+
+ inputs = [
+ changes_file,
+ script,
+ template_file,
+ ]
+ outputs = [
+ out_file
+ ]
+ args = [
+ rebase_path(src_dir, root_build_dir),
+ "-i", rebase_path(template_file, root_build_dir),
+ "-o", rebase_path(out_file, root_build_dir),
+ ]
+}
+
spirv_tools_dir = glslang_spirv_tools_dir
if (!defined(glslang_angle)) {
glslang_angle = false
@@ -109,7 +132,6 @@
"glslang/Include/Types.h",
"glslang/Include/arrays.h",
"glslang/Include/intermediate.h",
- "glslang/Include/revision.h",
"glslang/MachineIndependent/Constant.cpp",
"glslang/MachineIndependent/InfoSink.cpp",
"glslang/MachineIndependent/Initialize.cpp",
@@ -216,13 +238,18 @@
]
}
+ deps = [ ":glslang_build_info" ]
+
if (invoker.enable_opt) {
- deps = [
+ deps += [
+ ":glslang_build_info",
"${spirv_tools_dir}:spvtools_opt",
"${spirv_tools_dir}:spvtools_val",
]
}
+ include_dirs = [ "${target_gen_dir}/include" ]
+
configs -= _configs_to_remove
configs += _configs_to_add
}
@@ -265,6 +292,8 @@
]
public_configs = [ ":glslang_hlsl" ]
+ include_dirs = [ "${target_gen_dir}/include" ]
+
configs -= _configs_to_remove
configs += _configs_to_add
}