From dcaaa241dfb7ce77b7070df8d6a939a9f0749e2c Mon Sep 17 00:00:00 2001
From: "Matthew D. Steele" <mdsteele@alum.mit.edu>
Date: Fri, 3 Aug 2018 11:45:23 -0400
Subject: [PATCH] Fix a type error in std.os.linux.getpid() (#1326)

syscall0() returns usize, but we were trying to @bitCast to i32.
---
 std/os/linux/index.zig | 2 +-
 std/os/linux/test.zig  | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/std/os/linux/index.zig b/std/os/linux/index.zig
index 69bc30bad0..15607ea6c0 100644
--- a/std/os/linux/index.zig
+++ b/std/os/linux/index.zig
@@ -944,7 +944,7 @@ pub fn setgroups(size: usize, list: *const u32) usize {
 }
 
 pub fn getpid() i32 {
-    return @bitCast(i32, u32(syscall0(SYS_getpid)));
+    return @bitCast(i32, @truncate(u32, syscall0(SYS_getpid)));
 }
 
 pub fn sigprocmask(flags: u32, noalias set: *const sigset_t, noalias oldset: ?*sigset_t) usize {
diff --git a/std/os/linux/test.zig b/std/os/linux/test.zig
index e7dae3a584..4de26012c7 100644
--- a/std/os/linux/test.zig
+++ b/std/os/linux/test.zig
@@ -3,6 +3,10 @@ const builtin = @import("builtin");
 const linux = std.os.linux;
 const assert = std.debug.assert;
 
+test "getpid" {
+    assert(linux.getpid() != 0);
+}
+
 test "timer" {
     const epoll_fd = linux.epoll_create();
     var err = linux.getErrno(epoll_fd);