Auto merge of #1567 - glaubitz:sparc-linux, r=gnzlbg

Add initial support for sparc-unknown-linux-gnu

While the Rust compiler already supports the sparc-unknown-linux-gnu target, the libc crate is missing support for it. Let's add it so that Rust can built for this target as well.

Author: bors

src/unix/linux_like/linux/align.rs

@@ -62,6 +62,7 @@ macro_rules! expand_align {
                                target_arch = "arm",
                                target_arch = "hexagon",
                                target_arch = "powerpc",
+                               target_arch = "sparc",
                                target_arch = "x86_64",
                                target_arch = "x86")),
                        repr(align(4)))]
@@ -70,6 +71,7 @@ macro_rules! expand_align {
                                    target_arch = "arm",
                                    target_arch = "hexagon",
                                    target_arch = "powerpc",
+                                   target_arch = "sparc",
                                    target_arch = "x86_64",
                                    target_arch = "x86"))),
                        repr(align(8)))]
@@ -83,6 +85,7 @@ macro_rules! expand_align {
                                target_arch = "arm",
                                target_arch = "hexagon",
                                target_arch = "powerpc",
+                               target_arch = "sparc",
                                target_arch = "x86_64",
                                target_arch = "x86")),
                        repr(align(4)))]
@@ -91,6 +94,7 @@ macro_rules! expand_align {
                                    target_arch = "arm",
                                    target_arch = "hexagon",
                                    target_arch = "powerpc",
+                                   target_arch = "sparc",
                                    target_arch = "x86_64",
                                    target_arch = "x86"))),
                        repr(align(8)))]

src/unix/linux_like/linux/gnu/b32/mod.rs

@@ -262,6 +262,9 @@ cfg_if! {
     } else if #[cfg(target_arch = "powerpc")] {
         mod powerpc;
         pub use self::powerpc::*;
+    } else if #[cfg(target_arch = "sparc")] {
+        mod sparc;
+        pub use self::sparc::*;
     } else {
         // Unknown target_arch
     }

src/unix/linux_like/linux/gnu/b32/sparc/align.rs

@@ -0,0 +1,7 @@
+s_no_extra_traits! {
+    #[allow(missing_debug_implementations)]
+    #[repr(align(8))]
+    pub struct max_align_t {
+        priv_: [i64; 3]
+    }
+}