[RFC PATCH 0/2] meson: Specify Rust edition by rust_std=20XX

[RFC PATCH 0/2] meson: Specify Rust edition by rust_std=20XX

[Junjie Mao]

The official way to specify Rust edition in meson is the rust_std build option
[1]. It is used for generating --edition rustc options and filling
rust-project.json which provides project layout information to
rust-analyzer. Specifying Rust edition by rust_args instead causes meson to
generate "edition": "--edition" in rust-project.json, which is invalid.

Replace "--edition" rust_args with overriding of rust_std and build.rust_std to
fix the generated rust-project.json.

The rust_std option is part of the build environment and has two forms: rust_std
for the host machine and build.rust_std for the build machine. Specify both in
meson.build for completeness.

The default_options argument of project() is not used because it does not work
for rust_std in subprojects in meson 1.5.1.

This series is based on Paolo's refinement [2] to Manos's rust-pl011-rfc-v6
[3]. Feel free to squash these changes into that series.

[1] https://github.com/mesonbuild/meson/pull/7934
[2] https://gitlab.com/bonzini/qemu/-/tree/rust-for-manos
[3] https://lore.kernel.org/qemu-devel/rust-pl011-rfc-v6.git.manos.pitsidianakis@linaro.org

Junjie Mao (2):
  meson: subprojects: Specify Rust edition by rust_std=20XX
  rust: Specify Rust edition by rust_std=20XX

 rust/hw/char/pl011/meson.build                                | 4 +---
 rust/meson.build                                              | 4 +---
 rust/qemu-api/meson.build                                     | 2 +-
 subprojects/packagefiles/arbitrary-int-1-rs/meson.build       | 4 +---
 subprojects/packagefiles/bilge-impl-0.2-rs/meson.build        | 2 +-
 subprojects/packagefiles/either-1-rs/meson.build              | 2 +-
 subprojects/packagefiles/itertools-0.11-rs/meson.build        | 2 +-
 subprojects/packagefiles/proc-macro-error-1-rs/meson.build    | 2 +-
 .../packagefiles/proc-macro-error-attr-1-rs/meson.build       | 2 +-
 subprojects/packagefiles/proc-macro2-1-rs/meson.build         | 2 +-
 subprojects/packagefiles/quote-1-rs/meson.build               | 2 +-
 subprojects/packagefiles/syn-2-rs/meson.build                 | 2 +-
 subprojects/packagefiles/unicode-ident-1-rs/meson.build       | 4 +---
 13 files changed, 13 insertions(+), 21 deletions(-)

--
2.30.2

[RFC PATCH 1/2] meson: subprojects: Specify Rust edition by rust_std=20XX

[Junjie Mao]

Signed-off-by: Junjie Mao <junjie.mao@intel.com>
---
 subprojects/packagefiles/arbitrary-int-1-rs/meson.build       | 4 +---
 subprojects/packagefiles/bilge-impl-0.2-rs/meson.build        | 2 +-
 subprojects/packagefiles/either-1-rs/meson.build              | 2 +-
 subprojects/packagefiles/itertools-0.11-rs/meson.build        | 2 +-
 subprojects/packagefiles/proc-macro-error-1-rs/meson.build    | 2 +-
 .../packagefiles/proc-macro-error-attr-1-rs/meson.build       | 2 +-
 subprojects/packagefiles/proc-macro2-1-rs/meson.build         | 2 +-
 subprojects/packagefiles/quote-1-rs/meson.build               | 2 +-
 subprojects/packagefiles/syn-2-rs/meson.build                 | 2 +-
 subprojects/packagefiles/unicode-ident-1-rs/meson.build       | 4 +---
 10 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/subprojects/packagefiles/arbitrary-int-1-rs/meson.build b/subprojects/packagefiles/arbitrary-int-1-rs/meson.build
index 9cba82365f..34a189cbae 100644
--- a/subprojects/packagefiles/arbitrary-int-1-rs/meson.build
+++ b/subprojects/packagefiles/arbitrary-int-1-rs/meson.build
@@ -7,10 +7,8 @@ _arbitrary_int_rs = static_library(
   'arbitrary_int',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
-  rust_args: [
-    '--edition', '2021',
-  ],
   dependencies: [],
 )

diff --git a/subprojects/packagefiles/bilge-impl-0.2-rs/meson.build b/subprojects/packagefiles/bilge-impl-0.2-rs/meson.build
index e0c51c7375..80243c7024 100644
--- a/subprojects/packagefiles/bilge-impl-0.2-rs/meson.build
+++ b/subprojects/packagefiles/bilge-impl-0.2-rs/meson.build
@@ -22,8 +22,8 @@ rust = import('rust')
 _bilge_impl_rs = rust.proc_macro(
   'bilge_impl',
   files('src/lib.rs'),
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_args: [
-    '--edition', '2021',
     '--cfg', 'use_fallback',
     '--cfg', 'feature="syn-error"',
     '--cfg', 'feature="proc-macro"',
diff --git a/subprojects/packagefiles/either-1-rs/meson.build b/subprojects/packagefiles/either-1-rs/meson.build
index 07240b8708..a5842eb3a6 100644
--- a/subprojects/packagefiles/either-1-rs/meson.build
+++ b/subprojects/packagefiles/either-1-rs/meson.build
@@ -7,9 +7,9 @@ _either_rs = static_library(
   'either',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2018', 'build.rust_std=2018'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2018',
     '--cfg', 'feature="use_std"',
     '--cfg', 'feature="use_alloc"',
   ],
diff --git a/subprojects/packagefiles/itertools-0.11-rs/meson.build b/subprojects/packagefiles/itertools-0.11-rs/meson.build
index da731ca032..13d2d27019 100644
--- a/subprojects/packagefiles/itertools-0.11-rs/meson.build
+++ b/subprojects/packagefiles/itertools-0.11-rs/meson.build
@@ -11,9 +11,9 @@ _itertools_rs = static_library(
   'itertools',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2018', 'build.rust_std=2018'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2018',
     '--cfg', 'feature="use_std"',
     '--cfg', 'feature="use_alloc"',
   ],
diff --git a/subprojects/packagefiles/proc-macro-error-1-rs/meson.build b/subprojects/packagefiles/proc-macro-error-1-rs/meson.build
index 20f2e99a87..38ea7b89d3 100644
--- a/subprojects/packagefiles/proc-macro-error-1-rs/meson.build
+++ b/subprojects/packagefiles/proc-macro-error-1-rs/meson.build
@@ -16,9 +16,9 @@ syn_dep = dependency('syn-2-rs', native: true)
 _proc_macro_error_rs = static_library(
   'proc_macro_error',
   files('src/lib.rs'),
+  override_options: ['rust_std=2018', 'build.rust_std=2018'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2018',
     '--cfg', 'use_fallback',
     '--cfg', 'feature="syn-error"',
     '--cfg', 'feature="proc-macro"',
diff --git a/subprojects/packagefiles/proc-macro-error-attr-1-rs/meson.build b/subprojects/packagefiles/proc-macro-error-attr-1-rs/meson.build
index 1aafd41795..d900c54cfd 100644
--- a/subprojects/packagefiles/proc-macro-error-attr-1-rs/meson.build
+++ b/subprojects/packagefiles/proc-macro-error-attr-1-rs/meson.build
@@ -13,8 +13,8 @@ rust = import('rust')
 _proc_macro_error_attr_rs = rust.proc_macro(
   'proc_macro_error_attr',
   files('src/lib.rs'),
+  override_options: ['rust_std=2018', 'build.rust_std=2018'],
   rust_args: [
-    '--edition', '2018',
     '--cfg', 'use_fallback',
     '--cfg', 'feature="syn-error"',
     '--cfg', 'feature="proc-macro"'
diff --git a/subprojects/packagefiles/proc-macro2-1-rs/meson.build b/subprojects/packagefiles/proc-macro2-1-rs/meson.build
index 6796d75295..8e601b50cc 100644
--- a/subprojects/packagefiles/proc-macro2-1-rs/meson.build
+++ b/subprojects/packagefiles/proc-macro2-1-rs/meson.build
@@ -11,9 +11,9 @@ _proc_macro2_rs = static_library(
   'proc_macro2',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2021',
     '--cfg', 'feature="proc-macro"',
     '--cfg', 'no_literal_byte_character',
     '--cfg', 'no_literal_c_string',
diff --git a/subprojects/packagefiles/quote-1-rs/meson.build b/subprojects/packagefiles/quote-1-rs/meson.build
index a9c2fb9b61..d36609bd3c 100644
--- a/subprojects/packagefiles/quote-1-rs/meson.build
+++ b/subprojects/packagefiles/quote-1-rs/meson.build
@@ -11,9 +11,9 @@ _quote_rs = static_library(
   'quote',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2021',
     '--cfg', 'feature="proc-macro"',
   ],
   dependencies: [
diff --git a/subprojects/packagefiles/syn-2-rs/meson.build b/subprojects/packagefiles/syn-2-rs/meson.build
index b4666473fb..a53335f309 100644
--- a/subprojects/packagefiles/syn-2-rs/meson.build
+++ b/subprojects/packagefiles/syn-2-rs/meson.build
@@ -15,9 +15,9 @@ _syn_rs = static_library(
   'syn',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
   rust_args: [
-    '--edition', '2021',
     '--cfg', 'feature="full"',
     '--cfg', 'feature="derive"',
     '--cfg', 'feature="parsing"',
diff --git a/subprojects/packagefiles/unicode-ident-1-rs/meson.build b/subprojects/packagefiles/unicode-ident-1-rs/meson.build
index 77c581f40a..54f2376854 100644
--- a/subprojects/packagefiles/unicode-ident-1-rs/meson.build
+++ b/subprojects/packagefiles/unicode-ident-1-rs/meson.build
@@ -7,10 +7,8 @@ _unicode_ident_rs = static_library(
   'unicode_ident',
   files('src/lib.rs'),
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
-  rust_args: [
-    '--edition', '2021',
-  ],
   dependencies: [],
   native: true,
 )
--
2.30.2

[RFC PATCH 2/2] rust: Specify Rust edition by rust_std=20XX

[Junjie Mao]

Signed-off-by: Junjie Mao <junjie.mao@intel.com>
---
 rust/hw/char/pl011/meson.build | 4 +---
 rust/meson.build               | 4 +---
 rust/qemu-api/meson.build      | 2 +-
 3 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/rust/hw/char/pl011/meson.build b/rust/hw/char/pl011/meson.build
index 1c139d3af9..518d4924a9 100644
--- a/rust/hw/char/pl011/meson.build
+++ b/rust/hw/char/pl011/meson.build
@@ -7,10 +7,8 @@ bilge_impl_dep = dependency('bilge-impl-0.2-rs')
 _libpl011_rs = static_library(
   'pl011',
   files('src/lib.rs'),
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'c',
-  rust_args: rust_args + [
-    '--edition', '2021',
-  ],
   dependencies: [
     bilge_dep,
     bilge_impl_dep,
diff --git a/rust/meson.build b/rust/meson.build
index c321fa455e..590e9397c3 100644
--- a/rust/meson.build
+++ b/rust/meson.build
@@ -2,10 +2,8 @@ _lib_bindings_rs = static_library(
   '_bindings_rs',
   bindings_rs,
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
-  rust_args: rust_args + [
-    '--edition', '2021',
-  ],
 )

 subdir('qemu-api')
diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build
index a169872026..997d478309 100644
--- a/rust/qemu-api/meson.build
+++ b/rust/qemu-api/meson.build
@@ -2,9 +2,9 @@ _qemu_api_rs = static_library(
   'qemu_api',
   [files('src/lib.rs')],
   gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
   rust_abi: 'rust',
   rust_args: rust_args + [
-    '--edition', '2021',
     '--cfg', 'MESON_BINDINGS_RS',
   ],
   link_with: [
--
2.30.2

Re: [RFC PATCH 0/2] meson: Specify Rust edition by rust_std=20XX

[Manos Pitsidianakis]

On Wed, 14 Aug 2024 12:08, Junjie Mao <junjie.mao@intel.com> wrote:
>The official way to specify Rust edition in meson is the rust_std build option
>[1]. It is used for generating --edition rustc options and filling
>rust-project.json which provides project layout information to
>rust-analyzer. Specifying Rust edition by rust_args instead causes meson to
>generate "edition": "--edition" in rust-project.json, which is invalid.
>
>Replace "--edition" rust_args with overriding of rust_std and build.rust_std to
>fix the generated rust-project.json.
>
>The rust_std option is part of the build environment and has two forms: rust_std
>for the host machine and build.rust_std for the build machine. Specify both in
>meson.build for completeness.
>
>The default_options argument of project() is not used because it does not work
>for rust_std in subprojects in meson 1.5.1.
>
>This series is based on Paolo's refinement [2] to Manos's rust-pl011-rfc-v6
>[3]. Feel free to squash these changes into that series.
>
>[1] https://github.com/mesonbuild/meson/pull/7934
>[2] https://gitlab.com/bonzini/qemu/-/tree/rust-for-manos
>[3] https://lore.kernel.org/qemu-devel/rust-pl011-rfc-v6.git.manos.pitsidianakis@linaro.org
>
>Junjie Mao (2):
>  meson: subprojects: Specify Rust edition by rust_std=20XX
>  rust: Specify Rust edition by rust_std=20XX
>
> rust/hw/char/pl011/meson.build                                | 4 +---
> rust/meson.build                                              | 4 +---
> rust/qemu-api/meson.build                                     | 2 +-
> subprojects/packagefiles/arbitrary-int-1-rs/meson.build       | 4 +---
> subprojects/packagefiles/bilge-impl-0.2-rs/meson.build        | 2 +-
> subprojects/packagefiles/either-1-rs/meson.build              | 2 +-
> subprojects/packagefiles/itertools-0.11-rs/meson.build        | 2 +-
> subprojects/packagefiles/proc-macro-error-1-rs/meson.build    | 2 +-
> .../packagefiles/proc-macro-error-attr-1-rs/meson.build       | 2 +-
> subprojects/packagefiles/proc-macro2-1-rs/meson.build         | 2 +-
> subprojects/packagefiles/quote-1-rs/meson.build               | 2 +-
> subprojects/packagefiles/syn-2-rs/meson.build                 | 2 +-
> subprojects/packagefiles/unicode-ident-1-rs/meson.build       | 4 +---
> 13 files changed, 13 insertions(+), 21 deletions(-)
>
>--
>2.30.2

Thank you Junjie, I have applied the changes to the next version I will 
be posting. Cheers!

Manos