Fix build on musl and test it in CI

.github/workflows/ci.yaml

@@ -88,11 +88,14 @@ jobs:
       if: matrix.os == 'windows-latest'
       run: Remove-Item ./target/debug/xtask.exe, ./target/debug/deps/xtask.exe
 
-  # Weird target to catch non-portable code
-  rust-power:
-    name: Rust Power
+  # Weird targets to catch non-portable code
+  rust-cross:
+    name: Rust Cross
     runs-on: ubuntu-latest
 
+    env:
+      targets: "powerpc-unknown-linux-gnu x86_64-unknown-linux-musl"
+
     steps:
     - name: Checkout repository
       uses: actions/checkout@v2
@@ -103,7 +106,9 @@ jobs:
         toolchain: stable
         profile: minimal
         override: true
-        target: 'powerpc-unknown-linux-gnu'
+
+    - name: Install Rust targets
+      run: rustup target add ${{ env.targets }}
 
     - name: Cache cargo directories
       uses: actions/cache@v2
@@ -114,7 +119,10 @@ jobs:
         key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
     - name: Check
-      run: cargo check --target=powerpc-unknown-linux-gnu --all-targets
+      run: |
+        for target in ${{ env.targets }}; do
+          cargo check --target=$target --all-targets
+        done
 
   typescript:
     name: TypeScript

Cargo.lock

@@ -852,9 +852,9 @@ dependencies = [
 
 [[package]]
 name = "perf-event-open-sys"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "95db63e37862bc1b842135d2234ef9418f222cc660c6752f45e7cf9ddfb97f96"
+checksum = "83e7183862f36d10263d0a1ccaef50fef734ade948bf026afd1bd97355c78273"
 dependencies = [
  "libc",
 ]

crates/ra_prof/src/memory_usage.rs

@@ -24,7 +24,7 @@ impl std::ops::Sub for MemoryUsage {
 impl MemoryUsage {
     pub fn current() -> MemoryUsage {
         cfg_if! {
-            if #[cfg(target_os = "linux")] {
+            if #[cfg(all(target_os = "linux", target_env = "gnu"))] {
                 // Note: This is incredibly slow.
                 let alloc = unsafe { libc::mallinfo() }.uordblks as isize;
                 MemoryUsage { allocated: Bytes(alloc) }