Auto merge of #38675 - infinity0:more-jemalloc-fixes, r=alexcrichton

More jemalloc fixes

- Disable jemalloc on s390x as well (closes #38596)
- Disable jemalloc tests on platforms where it is disabled (closes #38612)

Author: bors

src/librustc_back/target/s390x_unknown_linux_gnu.rs

@@ -19,6 +19,8 @@ pub fn target() -> TargetResult {
     // Pass the -vector feature string to LLVM to respect this assumption.
     base.features = "-vector".to_string();
     base.max_atomic_width = Some(64);
+    // see #36994
+    base.exe_allocation_crate = "alloc_system".to_string();
 
     Ok(Target {
         llvm_target: "s390x-unknown-linux-gnu".to_string(),

src/test/compile-fail/allocator-rust-dylib-is-jemalloc.rs

@@ -29,9 +29,11 @@ extern crate allocator_dylib2;
 // ensure we get the same error.
 //
 // So long as we CI linux/OSX we should be good.
-#[cfg(any(target_os = "linux", target_os = "macos"))]
+#[cfg(any(all(target_os = "linux", any(target_arch = "x86", target_arch = "x86_64")),
+          target_os = "macos"))]
 extern crate alloc_system;
-#[cfg(not(any(target_os = "linux", target_os = "macos")))]
+#[cfg(not(any(all(target_os = "linux", any(target_arch = "x86", target_arch = "x86_64")),
+              target_os = "macos")))]
 extern crate allocator1;
 
 fn main() {

src/test/run-pass/allocator-default.rs

@@ -10,7 +10,8 @@
 
 #![feature(alloc_jemalloc)]
 
-#[cfg(any(target_os = "linux", target_os = "macos"))]
+#[cfg(any(all(target_os = "linux", any(target_arch = "x86", target_arch = "x86_64")),
+          target_os = "macos"))]
 extern crate alloc_jemalloc;
 
 fn main() {