Bug 1730397 - Update packed_simd to a version that supports rustc >= …

…1.56. r=hsivonen

Differential Revision: https://phabricator.services.mozilla.com/D125604

.cargo/config.in

@@ -69,7 +69,7 @@ rev = "746743227485a83123784df0c53227ab466612ed"
 [source."https://github.com/hsivonen/packed_simd"]
 git = "https://github.com/hsivonen/packed_simd"
 replace-with = "vendored-sources"
-rev = "6a16f954950401b92b4e220fbf2dfaf6f00e1fb2"
+rev = "8b4bd7d8229660a749dbe419a57ea01df9de5453"
 
 [source."https://github.com/hsivonen/chardetng_c"]
 git = "https://github.com/hsivonen/chardetng_c"

Cargo.toml

@@ -81,7 +81,7 @@ opt-level = 2
 chardetng = { git = "https://github.com/hsivonen/chardetng", rev="302c995f91f44cf26e77dc4758ad56c3ff0153ad" }
 chardetng_c = { git = "https://github.com/hsivonen/chardetng_c", rev="ed8a4c6f900a90d4dbc1d64b856e61490a1c3570" }
 libudev-sys = { path = "dom/webauthn/libudev-sys" }
-packed_simd = { git = "https://github.com/hsivonen/packed_simd", rev="6a16f954950401b92b4e220fbf2dfaf6f00e1fb2" }
+packed_simd = { git = "https://github.com/hsivonen/packed_simd", rev="8b4bd7d8229660a749dbe419a57ea01df9de5453" }
 minidump_writer_linux = { git = "https://github.com/msirringhaus/minidump_writer_linux.git", rev = "029ac0d54b237f27dc7d8d4e51bc0fb076e5e852" }
 # The following overrides point to dummy projects, as a temporary measure until this is resolved:
 # https://github.com/rust-lang/cargo/issues/6179

third_party/rust/packed_simd/Cargo.toml

@@ -29,6 +29,9 @@ default = []
 into_bits = []
 libcore_neon = []
 
+[build-dependencies]
+rustc_version = "0.2"
+
 [dev-dependencies]
 paste = "^0.1.3"
 arrayvec = { version = "^0.5", default-features = false }

third_party/rust/packed_simd/build.rs

@@ -1,8 +1,34 @@
+use rustc_version::{version_meta, Channel, Version};
+
 fn main() {
     println!("cargo:rustc-env=RUSTC_BOOTSTRAP=1");
     let target = std::env::var("TARGET")
         .expect("TARGET environment variable not defined");
     if target.contains("neon") {
         println!("cargo:rustc-cfg=libcore_neon");
     }
+    let ver_meta = version_meta().unwrap();
+    let old_const_generics =
+        if ver_meta.semver < Version::parse("1.56.0-alpha").unwrap() {
+            true
+        } else if ver_meta.semver >= Version::parse("1.57.0-alpha").unwrap() {
+            false
+        } else {
+            match ver_meta.channel {
+                Channel::Stable | Channel::Beta => false,
+                Channel::Nightly | Channel::Dev
+                    if ver_meta
+                        .commit_date
+                        .as_deref()
+                        .map(|d| d < "2021-08-31")
+                        .unwrap_or(false) =>
+                {
+                    true
+                }
+                _ => false,
+            }
+        };
+    if old_const_generics {
+        println!("cargo:rustc-cfg=const_generics");
+    }
 }

third_party/rust/packed_simd/src/lib.rs

@@ -199,8 +199,9 @@
 //!   Numeric casts are not very "precise": sometimes lossy, sometimes value
 //!   preserving, etc.
 
+#![cfg_attr(const_generics, feature(const_generics))]
+#![cfg_attr(not(const_generics), feature(adt_const_params))]
 #![feature(
-    const_generics,
     repr_simd,
     rustc_attrs,
     platform_intrinsics,