Update the libc submodule

Brings in a few fixes for wasm/asmjs

3 files changed, 27 insertions, 8 deletions

diff --git a/src/libstd/sys/unix/fd.rs b/src/libstd/sys/unix/fd.rs
index 138087f1651..f50b093acc8 100644
--- a/src/libstd/sys/unix/fd.rs
+++ b/src/libstd/sys/unix/fd.rs
@@ -71,13 +71,21 @@ impl FileDesc {
         #[cfg(target_os = "android")]
         use super::android::cvt_pread64;
 
-        #[cfg(not(target_os = "android"))]
+        #[cfg(target_os = "emscripten")]
         unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: usize, offset: i64)
             -> io::Result<isize>
         {
-            #[cfg(any(target_os = "linux", target_os = "emscripten"))]
             use libc::pread64;
-            #[cfg(not(any(target_os = "linux", target_os = "emscripten")))]
+            cvt(pread64(fd, buf, count, offset as i32))
+        }
+
+        #[cfg(not(any(target_os = "android", target_os = "emscripten")))]
+        unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: usize, offset: i64)
+            -> io::Result<isize>
+        {
+            #[cfg(target_os = "linux")]
+            use libc::pread64;
+            #[cfg(not(target_os = "linux"))]
             use libc::pread as pread64;
             cvt(pread64(fd, buf, count, offset))
         }
@@ -104,13 +112,21 @@ impl FileDesc {
         #[cfg(target_os = "android")]
         use super::android::cvt_pwrite64;
 
-        #[cfg(not(target_os = "android"))]
+        #[cfg(target_os = "emscripten")]
+        unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: usize, offset: i64)
+            -> io::Result<isize>
+        {
+            use libc::pwrite64;
+            cvt(pwrite64(fd, buf, count, offset as i32))
+        }
+
+        #[cfg(not(any(target_os = "android", target_os = "emscripten")))]
         unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: usize, offset: i64)
             -> io::Result<isize>
         {
-            #[cfg(any(target_os = "linux", target_os = "emscripten"))]
+            #[cfg(target_os = "linux")]
             use libc::pwrite64;
-            #[cfg(not(any(target_os = "linux", target_os = "emscripten")))]
+            #[cfg(not(target_os = "linux"))]
             use libc::pwrite as pwrite64;
             cvt(pwrite64(fd, buf, count, offset))
         }
diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index cb0f687e072..f94af491332 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -514,6 +514,8 @@ impl File {
             SeekFrom::End(off) => (libc::SEEK_END, off),
             SeekFrom::Current(off) => (libc::SEEK_CUR, off),
         };
+        #[cfg(target_os = "emscripten")]
+        let pos = pos as i32;
         let n = cvt(unsafe { lseek64(self.0.raw(), pos, whence) })?;
         Ok(n as u64)
     }
diff --git a/src/libstd/sys/unix/process/process_unix.rs b/src/libstd/sys/unix/process/process_unix.rs
index edd322ca6fa..ae24021fb6c 100644
--- a/src/libstd/sys/unix/process/process_unix.rs
+++ b/src/libstd/sys/unix/process/process_unix.rs
@@ -10,7 +10,6 @@
 
 use io::{self, Error, ErrorKind};
 use libc::{self, c_int, gid_t, pid_t, uid_t};
-use mem;
 use ptr;
 
 use sys::cvt;
@@ -184,7 +183,9 @@ impl Command {
         }
 
         // NaCl has no signal support.
-        if cfg!(not(any(target_os = "nacl", target_os = "emscripten"))) {
+        #[cfg(not(any(target_os = "nacl", target_os = "emscripten")))]
+        {
+            use mem;
             // Reset signal handling so the child process starts in a
             // standardized state. libstd ignores SIGPIPE, and signal-handling
             // libraries often set a mask. Child processes inherit ignored