adding aligned_alloc support for unixes.

close #3689

Author: devnexen

libc-test/build.rs

@@ -1936,6 +1936,9 @@ fn test_android(target: &str) {
             // Added in API level 28, but some tests use level 24.
             "fread_unlocked" | "fwrite_unlocked" | "fgets_unlocked" | "fflush_unlocked" => true,
 
+            // Added in API level 28, but some tests use level 24.
+            "aligned_alloc" => true,
+
             // FIXME: bad function pointers:
             "isalnum" | "isalpha" | "iscntrl" | "isdigit" | "isgraph" | "islower" | "isprint"
             | "ispunct" | "isspace" | "isupper" | "isxdigit" | "isblank" | "tolower"

libc-test/semver/unix.txt

@@ -452,6 +452,7 @@ accept
 access
 addrinfo
 alarm
+aligned_alloc
 atexit
 atof
 atoi

src/unix/mod.rs

@@ -896,6 +896,7 @@ extern "C" {
     pub fn pathconf(path: *const c_char, name: ::c_int) -> c_long;
     pub fn pipe(fds: *mut ::c_int) -> ::c_int;
     pub fn posix_memalign(memptr: *mut *mut ::c_void, align: ::size_t, size: ::size_t) -> ::c_int;
+    pub fn aligned_alloc(alignment: ::size_t, size: ::size_t) -> *mut ::c_void;
     #[cfg_attr(
         all(target_os = "macos", target_arch = "x86"),
         link_name = "read$UNIX2003"