Merge #922 #926

922: When building for linux, replace all vendors with 'unknown' r=taiki-e a=kanavin

Some build systems such as the Yocto project define custom rust targets, of the form 'arch-somevendor-linux-{gnu|musl}' (only the 'somevendor' part is custom, the rest matches rust's definitions).

This causes mismatches with crossbeam's lists of targets which are built from the standard rust target list, and always have 'unknown' as the vendor.

This change simply replaces such custom vendors with 'unknown' when the third component of the target is 'linux'.

---
Note from Alex: this is a reworked and hopefully better/more precise/acceptable version of #751

926: crossbeam-epoch: Bump memoffset to 0.7 r=taiki-e a=glittershark

mostly to keep the number of dupes of crates in my dependency graph down

Co-authored-by: Alexander Kanavin <alex@linutronix.de>
Co-authored-by: Griffin Smith <root@gws.fyi>

build-common.rs

@@ -0,0 +1,13 @@
+// The target triplets have the form of 'arch-vendor-system'.
+//
+// When building for Linux (e.g. the 'system' part is
+// 'linux-something'), replace the vendor with 'unknown'
+// so that mapping to rust standard targets happens correctly.
+fn convert_custom_linux_target(target: String) -> String {
+    let mut parts: Vec<&str> = target.split('-').collect();
+    let system = parts[2];
+    if system == "linux" {
+        parts[1] = "unknown";
+    };
+    parts.join("-")
+}

crossbeam-epoch/Cargo.toml

@@ -38,7 +38,7 @@ autocfg = "1"
 
 [dependencies]
 cfg-if = "1"
-memoffset = "0.6"
+memoffset = "0.7"
 scopeguard = { version = "1.1", default-features = false }
 
 # Enable the use of loom for concurrency testing.

crossbeam-epoch/build-common.rs

@@ -0,0 +1 @@
+../build-common.rs

crossbeam-epoch/build.rs

@@ -15,10 +15,11 @@
 use std::env;
 
 include!("no_atomic.rs");
+include!("build-common.rs");
 
 fn main() {
     let target = match env::var("TARGET") {
-        Ok(target) => target,
+        Ok(target) => convert_custom_linux_target(target),
         Err(e) => {
             println!(
                 "cargo:warning={}: unable to get TARGET environment variable: {}",

crossbeam-queue/build-common.rs

@@ -0,0 +1 @@
+../build-common.rs

crossbeam-queue/build.rs

@@ -15,10 +15,11 @@
 use std::env;
 
 include!("no_atomic.rs");
+include!("build-common.rs");
 
 fn main() {
     let target = match env::var("TARGET") {
-        Ok(target) => target,
+        Ok(target) => convert_custom_linux_target(target),
         Err(e) => {
             println!(
                 "cargo:warning={}: unable to get TARGET environment variable: {}",

crossbeam-skiplist/build-common.rs

@@ -0,0 +1 @@
+../build-common.rs

crossbeam-skiplist/build.rs

@@ -15,10 +15,11 @@
 use std::env;
 
 include!("no_atomic.rs");
+include!("build-common.rs");
 
 fn main() {
     let target = match env::var("TARGET") {
-        Ok(target) => target,
+        Ok(target) => convert_custom_linux_target(target),
         Err(e) => {
             println!(
                 "cargo:warning={}: unable to get TARGET environment variable: {}",

crossbeam-utils/build-common.rs

@@ -0,0 +1 @@
+../build-common.rs

crossbeam-utils/build.rs

@@ -27,10 +27,11 @@
 use std::env;
 
 include!("no_atomic.rs");
+include!("build-common.rs");
 
 fn main() {
     let target = match env::var("TARGET") {
-        Ok(target) => target,
+        Ok(target) => convert_custom_linux_target(target),
         Err(e) => {
             println!(
                 "cargo:warning={}: unable to get TARGET environment variable: {}",