diff --git a/lib/std/c.zig b/lib/std/c.zig
index 5e88b1a7d3..6a2624a93e 100644
--- a/lib/std/c.zig
+++ b/lib/std/c.zig
@@ -57,6 +57,8 @@ pub usingnamespace switch (builtin.os.tag) {
     else => struct {},
 };
 
+pub const whence_t = if (builtin.os.tag == .wasi) std.os.wasi.whence_t else c_int;
+
 pub usingnamespace switch (builtin.os.tag) {
     .netbsd, .macos, .ios, .watchos, .tvos, .windows => struct {},
     else => struct {
@@ -106,7 +108,7 @@ pub extern "c" fn exit(code: c_int) noreturn;
 pub extern "c" fn _exit(code: c_int) noreturn;
 pub extern "c" fn isatty(fd: c.fd_t) c_int;
 pub extern "c" fn close(fd: c.fd_t) c_int;
-pub extern "c" fn lseek(fd: c.fd_t, offset: c.off_t, whence: c_int) c.off_t;
+pub extern "c" fn lseek(fd: c.fd_t, offset: c.off_t, whence: whence_t) c.off_t;
 pub extern "c" fn open(path: [*:0]const u8, oflag: c_uint, ...) c_int;
 pub extern "c" fn openat(fd: c_int, path: [*:0]const u8, oflag: c_uint, ...) c_int;
 pub extern "c" fn ftruncate(fd: c_int, length: c.off_t) c_int;
diff --git a/lib/std/c/darwin.zig b/lib/std/c/darwin.zig
index a658138a96..a3c57f5204 100644
--- a/lib/std/c/darwin.zig
+++ b/lib/std/c/darwin.zig
@@ -613,38 +613,26 @@ pub const MAP = struct {
     pub const FAILED = @intToPtr(*c_void, maxInt(usize));
 };
 
-/// [XSI] no hang in wait/no child to reap
-pub const WNOHANG = 0x00000001;
-
-/// [XSI] notify on stop, untraced child
-pub const WUNTRACED = 0x00000002;
-
-/// take signal on signal stack
-pub const SA_ONSTACK = 0x0001;
-
-/// restart system on signal return
-pub const SA_RESTART = 0x0002;
-
-/// reset to SIG.DFL when taking signal
-pub const SA_RESETHAND = 0x0004;
-
-/// do not generate SIG.CHLD on child stop
-pub const SA_NOCLDSTOP = 0x0008;
-
-/// don't mask the signal we're delivering
-pub const SA_NODEFER = 0x0010;
-
-/// don't keep zombies around
-pub const SA_NOCLDWAIT = 0x0020;
-
-/// signal handler with SA_SIGINFO args
-pub const SA_SIGINFO = 0x0040;
-
-/// do not bounce off kernel's sigtramp
-pub const SA_USERTRAMP = 0x0100;
-
-/// signal handler with SA_SIGINFO args with 64bit   regs information
-pub const SA_64REGSET = 0x0200;
+pub const SA = struct {
+    /// take signal on signal stack
+    pub const ONSTACK = 0x0001;
+    /// restart system on signal return
+    pub const RESTART = 0x0002;
+    /// reset to SIG.DFL when taking signal
+    pub const RESETHAND = 0x0004;
+    /// do not generate SIG.CHLD on child stop
+    pub const NOCLDSTOP = 0x0008;
+    /// don't mask the signal we're delivering
+    pub const NODEFER = 0x0010;
+    /// don't keep zombies around
+    pub const NOCLDWAIT = 0x0020;
+    /// signal handler with SIGINFO args
+    pub const SIGINFO = 0x0040;
+    /// do not bounce off kernel's sigtramp
+    pub const USERTRAMP = 0x0100;
+    /// signal handler with SIGINFO args with 64bit regs information
+    pub const @"64REGSET" = 0x0200;
+};
 
 pub const F_OK = 0;
 pub const X_OK = 1;
@@ -694,19 +682,23 @@ pub const O = struct {
     pub const SYNC = 128;
 };
 
-pub const SEEK_SET = 0x0;
-pub const SEEK_CUR = 0x1;
-pub const SEEK_END = 0x2;
+pub const SEEK = struct {
+    pub const SET = 0x0;
+    pub const CUR = 0x1;
+    pub const END = 0x2;
+};
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14;
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14;
+};
 
 /// no flag value
 pub const KEVENT_FLAG_NONE = 0x000;
@@ -1070,6 +1062,11 @@ pub const SO = struct {
 };
 
 pub const W = struct {
+    /// [XSI] no hang in wait/no child to reap
+    pub const NOHANG = 0x00000001;
+    /// [XSI] notify on stop, untraced child
+    pub const UNTRACED = 0x00000002;
+
     pub fn EXITSTATUS(x: u32) u8 {
         return @intCast(u8, x >> 8);
     }
@@ -1759,9 +1756,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 // Term
 pub const VEOF = 0;
diff --git a/lib/std/c/dragonfly.zig b/lib/std/c/dragonfly.zig
index 921116b4f6..d2356dbf2c 100644
--- a/lib/std/c/dragonfly.zig
+++ b/lib/std/c/dragonfly.zig
@@ -182,20 +182,43 @@ pub const MAP = struct {
     pub const SIZEALIGN = 262144;
 };
 
-pub const WNOHANG = 0x0001;
-pub const WUNTRACED = 0x0002;
-pub const WCONTINUED = 0x0004;
-pub const WSTOPPED = WUNTRACED;
-pub const WNOWAIT = 0x0008;
-pub const WEXITED = 0x0010;
-pub const WTRAPPED = 0x0020;
+pub const W = struct {
+    pub const NOHANG = 0x0001;
+    pub const UNTRACED = 0x0002;
+    pub const CONTINUED = 0x0004;
+    pub const STOPPED = UNTRACED;
+    pub const NOWAIT = 0x0008;
+    pub const EXITED = 0x0010;
+    pub const TRAPPED = 0x0020;
 
-pub const SA_ONSTACK = 0x0001;
-pub const SA_RESTART = 0x0002;
-pub const SA_RESETHAND = 0x0004;
-pub const SA_NODEFER = 0x0010;
-pub const SA_NOCLDWAIT = 0x0020;
-pub const SA_SIGINFO = 0x0040;
+    pub fn EXITSTATUS(s: u32) u8 {
+        return @intCast(u8, (s & 0xff00) >> 8);
+    }
+    pub fn TERMSIG(s: u32) u32 {
+        return s & 0x7f;
+    }
+    pub fn STOPSIG(s: u32) u32 {
+        return EXITSTATUS(s);
+    }
+    pub fn IFEXITED(s: u32) bool {
+        return TERMSIG(s) == 0;
+    }
+    pub fn IFSTOPPED(s: u32) bool {
+        return @intCast(u16, (((s & 0xffff) *% 0x10001) >> 8)) > 0x7f00;
+    }
+    pub fn IFSIGNALED(s: u32) bool {
+        return (s & 0xffff) -% 1 < 0xff;
+    }
+};
+
+pub const SA = struct {
+    pub const ONSTACK = 0x0001;
+    pub const RESTART = 0x0002;
+    pub const RESETHAND = 0x0004;
+    pub const NODEFER = 0x0010;
+    pub const NOCLDWAIT = 0x0020;
+    pub const SIGINFO = 0x0040;
+};
 
 pub const PATH_MAX = 1024;
 pub const IOV_MAX = KERN_IOV_MAX;
@@ -348,11 +371,13 @@ pub const O = struct {
     pub const DIRECTORY = 134217728;
 };
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
-pub const SEEK_DATA = 3;
-pub const SEEK_HOLE = 4;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+    pub const DATA = 3;
+    pub const HOLE = 4;
+};
 
 pub const F = struct {
     pub const ULOCK = 0;
@@ -388,25 +413,6 @@ pub const AT = struct {
     pub const SYMLINK_FOLLOW = 8;
 };
 
-pub fn WEXITSTATUS(s: u32) u8 {
-    return @intCast(u8, (s & 0xff00) >> 8);
-}
-pub fn WTERMSIG(s: u32) u32 {
-    return s & 0x7f;
-}
-pub fn WSTOPSIG(s: u32) u32 {
-    return WEXITSTATUS(s);
-}
-pub fn WIFEXITED(s: u32) bool {
-    return WTERMSIG(s) == 0;
-}
-pub fn WIFSTOPPED(s: u32) bool {
-    return @intCast(u16, (((s & 0xffff) *% 0x10001) >> 8)) > 0x7f00;
-}
-pub fn WIFSIGNALED(s: u32) bool {
-    return (s & 0xffff) -% 1 < 0xff;
-}
-
 pub const dirent = extern struct {
     d_fileno: c_ulong,
     d_namlen: u16,
@@ -420,16 +426,18 @@ pub const dirent = extern struct {
     }
 };
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14;
-pub const DT_DBF = 15;
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14;
+    pub const DBF = 15;
+};
 
 pub const CLOCK = struct {
     pub const REALTIME = 0;
@@ -1075,9 +1083,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 pub const nfds_t = u32;
 
diff --git a/lib/std/c/freebsd.zig b/lib/std/c/freebsd.zig
index 3e5fbf25fe..5ffc92e53a 100644
--- a/lib/std/c/freebsd.zig
+++ b/lib/std/c/freebsd.zig
@@ -569,9 +569,11 @@ pub const LOCK = struct {
 
 pub const FD_CLOEXEC = 1;
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+};
 
 pub const SOCK = struct {
     pub const STREAM = 1;
@@ -721,15 +723,17 @@ pub const AF = struct {
     pub const MAX = 42;
 };
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14;
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14;
+};
 
 /// add event to kq (implies enable)
 pub const EV_ADD = 0x0001;
@@ -1541,9 +1545,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 pub const nfds_t = u32;
 
diff --git a/lib/std/c/haiku.zig b/lib/std/c/haiku.zig
index e759ab10a4..b708d235a9 100644
--- a/lib/std/c/haiku.zig
+++ b/lib/std/c/haiku.zig
@@ -408,23 +408,52 @@ pub const MAP = struct {
     pub const PREFAULT_READ = 0x00040000;
     pub const @"32BIT" = 0x00080000;
 };
-pub const WNOHANG = 0x1;
-pub const WUNTRACED = 0x2;
-pub const WSTOPPED = 0x10;
-pub const WCONTINUED = 0x4;
-pub const WNOWAIT = 0x20;
-pub const WEXITED = 0x08;
 
-pub const SA_ONSTACK = 0x20;
-pub const SA_RESTART = 0x10;
-pub const SA_RESETHAND = 0x04;
-pub const SA_NOCLDSTOP = 0x01;
-pub const SA_NODEFER = 0x08;
-pub const SA_NOCLDWAIT = 0x02;
-pub const SA_SIGINFO = 0x40;
-pub const SA_NOMASK = SA_NODEFER;
-pub const SA_STACK = SA_ONSTACK;
-pub const SA_ONESHOT = SA_RESETHAND;
+pub const W = struct {
+    pub const NOHANG = 0x1;
+    pub const UNTRACED = 0x2;
+    pub const STOPPED = 0x10;
+    pub const CONTINUED = 0x4;
+    pub const NOWAIT = 0x20;
+    pub const EXITED = 0x08;
+
+    pub fn EXITSTATUS(s: u32) u8 {
+        return @intCast(u8, s & 0xff);
+    }
+
+    pub fn TERMSIG(s: u32) u32 {
+        return (s >> 8) & 0xff;
+    }
+
+    pub fn STOPSIG(s: u32) u32 {
+        return EXITSTATUS(s);
+    }
+
+    pub fn IFEXITED(s: u32) bool {
+        return TERMSIG(s) == 0;
+    }
+
+    pub fn IFSTOPPED(s: u32) bool {
+        return ((s >> 16) & 0xff) != 0;
+    }
+
+    pub fn IFSIGNALED(s: u32) bool {
+        return ((s >> 8) & 0xff) != 0;
+    }
+};
+
+pub const SA = struct {
+    pub const ONSTACK = 0x20;
+    pub const RESTART = 0x10;
+    pub const RESETHAND = 0x04;
+    pub const NOCLDSTOP = 0x01;
+    pub const NODEFER = 0x08;
+    pub const NOCLDWAIT = 0x02;
+    pub const SIGINFO = 0x40;
+    pub const NOMASK = NODEFER;
+    pub const STACK = ONSTACK;
+    pub const ONESHOT = RESETHAND;
+};
 
 pub const SIG = struct {
     pub const ERR = @intToPtr(fn (i32) callconv(.C) void, maxInt(usize));
@@ -558,9 +587,11 @@ pub const LOCK = struct {
 
 pub const FD_CLOEXEC = 1;
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+};
 
 pub const SOCK = struct {
     pub const STREAM = 1;
@@ -710,15 +741,17 @@ pub const AF = struct {
     pub const MAX = 42;
 };
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14;
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14;
+};
 
 /// add event to kq (implies enable)
 pub const EV_ADD = 0x0001;
@@ -806,32 +839,6 @@ pub const T = struct {
     pub const IOCGSID = 0x8024;
 };
 
-pub const W = struct {
-    pub fn EXITSTATUS(s: u32) u8 {
-        return @intCast(u8, s & 0xff);
-    }
-
-    pub fn TERMSIG(s: u32) u32 {
-        return (s >> 8) & 0xff;
-    }
-
-    pub fn STOPSIG(s: u32) u32 {
-        return EXITSTATUS(s);
-    }
-
-    pub fn IFEXITED(s: u32) bool {
-        return TERMSIG(s) == 0;
-    }
-
-    pub fn IFSTOPPED(s: u32) bool {
-        return ((s >> 16) & 0xff) != 0;
-    }
-
-    pub fn IFSIGNALED(s: u32) bool {
-        return ((s >> 8) & 0xff) != 0;
-    }
-};
-
 pub const winsize = extern struct {
     ws_row: u16,
     ws_col: u16,
@@ -1364,9 +1371,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 // TODO fill out if needed
 pub const directory_which = enum(c_int) {
diff --git a/lib/std/c/linux.zig b/lib/std/c/linux.zig
index 5ffdc37689..aa9d4087c2 100644
--- a/lib/std/c/linux.zig
+++ b/lib/std/c/linux.zig
@@ -96,6 +96,7 @@ pub const ucontext_t = linux.ucontext_t;
 pub const uid_t = linux.uid_t;
 pub const user_desc = linux.user_desc;
 pub const utsname = linux.utsname;
+pub const PR = linux.PR;
 
 pub const _errno = switch (native_abi) {
     .android => struct {
diff --git a/lib/std/c/netbsd.zig b/lib/std/c/netbsd.zig
index cf066f3f47..9dedf0997c 100644
--- a/lib/std/c/netbsd.zig
+++ b/lib/std/c/netbsd.zig
@@ -569,21 +569,51 @@ pub const MAP = struct {
     pub const ANONYMOUS = ANON;
     pub const STACK = 0x2000;
 };
-pub const WNOHANG = 0x00000001;
-pub const WUNTRACED = 0x00000002;
-pub const WSTOPPED = WUNTRACED;
-pub const WCONTINUED = 0x00000010;
-pub const WNOWAIT = 0x00010000;
-pub const WEXITED = 0x00000020;
-pub const WTRAPPED = 0x00000040;
 
-pub const SA_ONSTACK = 0x0001;
-pub const SA_RESTART = 0x0002;
-pub const SA_RESETHAND = 0x0004;
-pub const SA_NOCLDSTOP = 0x0008;
-pub const SA_NODEFER = 0x0010;
-pub const SA_NOCLDWAIT = 0x0020;
-pub const SA_SIGINFO = 0x0040;
+pub const W = struct {
+    pub const NOHANG = 0x00000001;
+    pub const UNTRACED = 0x00000002;
+    pub const STOPPED = UNTRACED;
+    pub const CONTINUED = 0x00000010;
+    pub const NOWAIT = 0x00010000;
+    pub const EXITED = 0x00000020;
+    pub const TRAPPED = 0x00000040;
+
+    pub fn EXITSTATUS(s: u32) u8 {
+        return @intCast(u8, (s >> 8) & 0xff);
+    }
+    pub fn TERMSIG(s: u32) u32 {
+        return s & 0x7f;
+    }
+    pub fn STOPSIG(s: u32) u32 {
+        return EXITSTATUS(s);
+    }
+    pub fn IFEXITED(s: u32) bool {
+        return TERMSIG(s) == 0;
+    }
+
+    pub fn IFCONTINUED(s: u32) bool {
+        return ((s & 0x7f) == 0xffff);
+    }
+
+    pub fn IFSTOPPED(s: u32) bool {
+        return ((s & 0x7f != 0x7f) and !IFCONTINUED(s));
+    }
+
+    pub fn IFSIGNALED(s: u32) bool {
+        return !IFSTOPPED(s) and !IFCONTINUED(s) and !IFEXITED(s);
+    }
+};
+
+pub const SA = struct {
+    pub const ONSTACK = 0x0001;
+    pub const RESTART = 0x0002;
+    pub const RESETHAND = 0x0004;
+    pub const NOCLDSTOP = 0x0008;
+    pub const NODEFER = 0x0010;
+    pub const NOCLDWAIT = 0x0020;
+    pub const SIGINFO = 0x0040;
+};
 
 // access function
 pub const F_OK = 0; // test for existence of file
@@ -666,19 +696,23 @@ pub const LOCK = struct {
 
 pub const FD_CLOEXEC = 1;
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+};
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14;
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14;
+};
 
 /// add event to kq (implies enable)
 pub const EV_ADD = 0x0001;
@@ -845,31 +879,6 @@ pub const T = struct {
     pub const IOCXMTFRAME = 0x80087444;
 };
 
-pub fn WEXITSTATUS(s: u32) u8 {
-    return @intCast(u8, (s >> 8) & 0xff);
-}
-pub fn WTERMSIG(s: u32) u32 {
-    return s & 0x7f;
-}
-pub fn WSTOPSIG(s: u32) u32 {
-    return WEXITSTATUS(s);
-}
-pub fn WIFEXITED(s: u32) bool {
-    return WTERMSIG(s) == 0;
-}
-
-pub fn WIFCONTINUED(s: u32) bool {
-    return ((s & 0x7f) == 0xffff);
-}
-
-pub fn WIFSTOPPED(s: u32) bool {
-    return ((s & 0x7f != 0x7f) and !WIFCONTINUED(s));
-}
-
-pub fn WIFSIGNALED(s: u32) bool {
-    return !WIFSTOPPED(s) and !WIFCONTINUED(s) and !WIFEXITED(s);
-}
-
 pub const winsize = extern struct {
     ws_row: u16,
     ws_col: u16,
@@ -1388,9 +1397,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 pub const nfds_t = u32;
 
diff --git a/lib/std/c/openbsd.zig b/lib/std/c/openbsd.zig
index 83a32d52e3..0ff7b904bd 100644
--- a/lib/std/c/openbsd.zig
+++ b/lib/std/c/openbsd.zig
@@ -361,17 +361,47 @@ pub const MAP = struct {
     pub const STACK = 0x4000;
     pub const CONCEAL = 0x8000;
 };
-pub const WNOHANG = 1;
-pub const WUNTRACED = 2;
-pub const WCONTINUED = 8;
 
-pub const SA_ONSTACK = 0x0001;
-pub const SA_RESTART = 0x0002;
-pub const SA_RESETHAND = 0x0004;
-pub const SA_NOCLDSTOP = 0x0008;
-pub const SA_NODEFER = 0x0010;
-pub const SA_NOCLDWAIT = 0x0020;
-pub const SA_SIGINFO = 0x0040;
+pub const W = struct {
+    pub const NOHANG = 1;
+    pub const UNTRACED = 2;
+    pub const CONTINUED = 8;
+
+    pub fn EXITSTATUS(s: u32) u8 {
+        return @intCast(u8, (s >> 8) & 0xff);
+    }
+    pub fn TERMSIG(s: u32) u32 {
+        return (s & 0x7f);
+    }
+    pub fn STOPSIG(s: u32) u32 {
+        return EXITSTATUS(s);
+    }
+    pub fn IFEXITED(s: u32) bool {
+        return TERMSIG(s) == 0;
+    }
+
+    pub fn IFCONTINUED(s: u32) bool {
+        return ((s & 0o177777) == 0o177777);
+    }
+
+    pub fn IFSTOPPED(s: u32) bool {
+        return (s & 0xff == 0o177);
+    }
+
+    pub fn IFSIGNALED(s: u32) bool {
+        return (((s) & 0o177) != 0o177) and (((s) & 0o177) != 0);
+    }
+};
+
+pub const SA = struct {
+    pub const ONSTACK = 0x0001;
+    pub const RESTART = 0x0002;
+    pub const RESETHAND = 0x0004;
+    pub const NOCLDSTOP = 0x0008;
+    pub const NODEFER = 0x0010;
+    pub const NOCLDWAIT = 0x0020;
+    pub const SIGINFO = 0x0040;
+};
 
 // access function
 pub const F_OK = 0; // test for existence of file
@@ -448,9 +478,11 @@ pub const LOCK = struct {
 
 pub const FD_CLOEXEC = 1;
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+};
 
 pub const SOCK = struct {
     pub const STREAM = 1;
@@ -530,15 +562,17 @@ pub const AF = struct {
     pub const MAX = 36;
 };
 
-pub const DT_UNKNOWN = 0;
-pub const DT_FIFO = 1;
-pub const DT_CHR = 2;
-pub const DT_DIR = 4;
-pub const DT_BLK = 6;
-pub const DT_REG = 8;
-pub const DT_LNK = 10;
-pub const DT_SOCK = 12;
-pub const DT_WHT = 14; // XXX
+pub const DT = struct {
+    pub const UNKNOWN = 0;
+    pub const FIFO = 1;
+    pub const CHR = 2;
+    pub const DIR = 4;
+    pub const BLK = 6;
+    pub const REG = 8;
+    pub const LNK = 10;
+    pub const SOCK = 12;
+    pub const WHT = 14; // XXX
+};
 
 pub const EV_ADD = 0x0001;
 pub const EV_DELETE = 0x0002;
@@ -668,31 +702,6 @@ pub const T = struct {
     pub const IOCXMTFRAME = 0x80087444;
 };
 
-pub fn WEXITSTATUS(s: u32) u8 {
-    return @intCast(u8, (s >> 8) & 0xff);
-}
-pub fn WTERMSIG(s: u32) u32 {
-    return (s & 0x7f);
-}
-pub fn WSTOPSIG(s: u32) u32 {
-    return WEXITSTATUS(s);
-}
-pub fn WIFEXITED(s: u32) bool {
-    return WTERMSIG(s) == 0;
-}
-
-pub fn WIFCONTINUED(s: u32) bool {
-    return ((s & 0o177777) == 0o177777);
-}
-
-pub fn WIFSTOPPED(s: u32) bool {
-    return (s & 0xff == 0o177);
-}
-
-pub fn WIFSIGNALED(s: u32) bool {
-    return (((s) & 0o177) != 0o177) and (((s) & 0o177) != 0);
-}
-
 pub const winsize = extern struct {
     ws_row: c_ushort,
     ws_col: c_ushort,
@@ -1178,9 +1187,11 @@ pub const rlimit = extern struct {
     max: rlim_t,
 };
 
-pub const SHUT_RD = 0;
-pub const SHUT_WR = 1;
-pub const SHUT_RDWR = 2;
+pub const SHUT = struct {
+    pub const RD = 0;
+    pub const WR = 1;
+    pub const RDWR = 2;
+};
 
 pub const nfds_t = c_uint;
 
diff --git a/lib/std/c/wasi.zig b/lib/std/c/wasi.zig
index 497f1213c8..d9fbed8e6d 100644
--- a/lib/std/c/wasi.zig
+++ b/lib/std/c/wasi.zig
@@ -8,7 +8,7 @@ pub fn _errno() *c_int {
     return &errno;
 }
 
-pub const fd_t = c_int;
+pub const fd_t = wasi.fd_t;
 pub const pid_t = c_int;
 pub const uid_t = u32;
 pub const gid_t = u32;
@@ -22,6 +22,9 @@ pub const STDIN_FILENO = wasi.STDIN_FILENO;
 pub const STDOUT_FILENO = wasi.STDOUT_FILENO;
 pub const E = wasi.E;
 pub const CLOCK = wasi.CLOCK;
+pub const S = wasi.S;
+pub const IOV_MAX = wasi.IOV_MAX;
+pub const AT = wasi.AT;
 
 pub const Stat = extern struct {
     dev: i32,
diff --git a/lib/std/c/windows.zig b/lib/std/c/windows.zig
index 3a5b033022..00cec5f5f7 100644
--- a/lib/std/c/windows.zig
+++ b/lib/std/c/windows.zig
@@ -88,9 +88,11 @@ pub const SIG = struct {
     pub const ERR = -1;
 };
 
-pub const SEEK_SET = 0;
-pub const SEEK_CUR = 1;
-pub const SEEK_END = 2;
+pub const SEEK = struct {
+    pub const SET = 0;
+    pub const CUR = 1;
+    pub const END = 2;
+};
 
 pub const E = enum(u16) {
     /// No error occurred.
diff --git a/lib/std/fs.zig b/lib/std/fs.zig
index 5c795e658f..3299ddafdc 100644
--- a/lib/std/fs.zig
+++ b/lib/std/fs.zig
@@ -344,7 +344,7 @@ pub const Dir = struct {
                         self.index = 0;
                         self.end_index = @intCast(usize, rc);
                     }
-                    const darwin_entry = @ptrCast(*align(1) os.dirent, &self.buf[self.index]);
+                    const darwin_entry = @ptrCast(*align(1) os.darwin.dirent, &self.buf[self.index]);
                     const next_index = self.index + darwin_entry.reclen();
                     self.index = next_index;
 
@@ -355,14 +355,14 @@ pub const Dir = struct {
                     }
 
                     const entry_kind = switch (darwin_entry.d_type) {
-                        os.DT_BLK => Entry.Kind.BlockDevice,
-                        os.DT_CHR => Entry.Kind.CharacterDevice,
-                        os.DT_DIR => Entry.Kind.Directory,
-                        os.DT_FIFO => Entry.Kind.NamedPipe,
-                        os.DT_LNK => Entry.Kind.SymLink,
-                        os.DT_REG => Entry.Kind.File,
-                        os.DT_SOCK => Entry.Kind.UnixDomainSocket,
-                        os.DT_WHT => Entry.Kind.Whiteout,
+                        os.DT.BLK => Entry.Kind.BlockDevice,
+                        os.DT.CHR => Entry.Kind.CharacterDevice,
+                        os.DT.DIR => Entry.Kind.Directory,
+                        os.DT.FIFO => Entry.Kind.NamedPipe,
+                        os.DT.LNK => Entry.Kind.SymLink,
+                        os.DT.REG => Entry.Kind.File,
+                        os.DT.SOCK => Entry.Kind.UnixDomainSocket,
+                        os.DT.WHT => Entry.Kind.Whiteout,
                         else => Entry.Kind.Unknown,
                     };
                     return Entry{
@@ -409,14 +409,14 @@ pub const Dir = struct {
                     }
 
                     const entry_kind = switch (bsd_entry.d_type) {
-                        os.DT_BLK => Entry.Kind.BlockDevice,
-                        os.DT_CHR => Entry.Kind.CharacterDevice,
-                        os.DT_DIR => Entry.Kind.Directory,
-                        os.DT_FIFO => Entry.Kind.NamedPipe,
-                        os.DT_LNK => Entry.Kind.SymLink,
-                        os.DT_REG => Entry.Kind.File,
-                        os.DT_SOCK => Entry.Kind.UnixDomainSocket,
-                        os.DT_WHT => Entry.Kind.Whiteout,
+                        os.DT.BLK => Entry.Kind.BlockDevice,
+                        os.DT.CHR => Entry.Kind.CharacterDevice,
+                        os.DT.DIR => Entry.Kind.Directory,
+                        os.DT.FIFO => Entry.Kind.NamedPipe,
+                        os.DT.LNK => Entry.Kind.SymLink,
+                        os.DT.REG => Entry.Kind.File,
+                        os.DT.SOCK => Entry.Kind.UnixDomainSocket,
+                        os.DT.WHT => Entry.Kind.Whiteout,
                         else => Entry.Kind.Unknown,
                     };
                     return Entry{
diff --git a/lib/std/fs/wasi.zig b/lib/std/fs/wasi.zig
index 5ace21ecd7..a6c6dac711 100644
--- a/lib/std/fs/wasi.zig
+++ b/lib/std/fs/wasi.zig
@@ -175,5 +175,5 @@ test "extracting WASI preopens" {
     try std.testing.expectEqual(@as(usize, 1), preopens.asSlice().len);
     const preopen = preopens.find(PreopenType{ .Dir = "." }) orelse unreachable;
     try std.testing.expect(preopen.@"type".eql(PreopenType{ .Dir = "." }));
-    try std.testing.expectEqual(@as(usize, 3), preopen.fd);
+    try std.testing.expectEqual(@as(i32, 3), preopen.fd);
 }
diff --git a/lib/std/os.zig b/lib/std/os.zig
index 1de4bac644..43062948bd 100644
--- a/lib/std/os.zig
+++ b/lib/std/os.zig
@@ -68,6 +68,7 @@ pub const ARCH = system.ARCH;
 pub const AT = system.AT;
 pub const CLOCK = system.CLOCK;
 pub const CPU_COUNT = system.CPU_COUNT;
+pub const DT = system.DT;
 pub const E = system.E;
 pub const Elf_Symndx = system.Elf_Symndx;
 pub const F = system.F;
diff --git a/lib/std/os/linux.zig b/lib/std/os/linux.zig
index 33d640a958..adce478cb8 100644
--- a/lib/std/os/linux.zig
+++ b/lib/std/os/linux.zig
@@ -105,18 +105,19 @@ pub const MAP = struct {
     /// Interpret addr exactly
     pub const FIXED = 0x10;
     /// don't use a file
-    pub const ANONYMOUS = 0x20;
+    pub const ANONYMOUS = if (is_mips) 0x800 else 0x20;
+    // MAP_ 0x0100 - 0x4000 flags are per architecture
     /// populate (prefault) pagetables
-    pub const POPULATE = 0x8000;
+    pub const POPULATE = if (is_mips) 0x10000 else 0x8000;
     /// do not block on IO
-    pub const NONBLOCK = 0x10000;
+    pub const NONBLOCK = if (is_mips) 0x20000 else 0x10000;
     /// give out an address that is best suited for process/thread stacks
-    pub const STACK = 0x20000;
+    pub const STACK = if (is_mips) 0x40000 else 0x20000;
     /// create a huge page mapping
-    pub const HUGETLB = 0x40000;
+    pub const HUGETLB = if (is_mips) 0x80000 else 0x40000;
     /// perform synchronous page faults for the mapping
     pub const SYNC = 0x80000;
-    /// FIXED which doesn't unmap underlying mapping
+    /// MAP_FIXED which doesn't unmap underlying mapping
     pub const FIXED_NOREPLACE = 0x100000;
     /// For anonymous mmap, memory could be uninitialized
     pub const UNINITIALIZED = 0x4000000;
@@ -2111,154 +2112,92 @@ pub const AF = struct {
     pub const MAX = PF.MAX;
 };
 
-pub const SO = if (is_mips) struct {
-    pub const SECURITY_AUTHENTICATION = 22;
-    pub const SECURITY_ENCRYPTION_TRANSPORT = 23;
-    pub const SECURITY_ENCRYPTION_NETWORK = 24;
-
-    pub const BINDTODEVICE = 25;
-
-    pub const ATTACH_FILTER = 26;
-    pub const DETACH_FILTER = 27;
-    pub const GET_FILTER = ATTACH_FILTER;
-
-    pub const PEERNAME = 28;
-    pub const TIMESTAMP_OLD = 29;
-    pub const PASSSEC = 34;
-    pub const TIMESTAMPNS_OLD = 35;
-    pub const MARK = 36;
-    pub const TIMESTAMPING_OLD = 37;
-
-    pub const RXQ_OVFL = 40;
-    pub const WIFI_STATUS = 41;
-    pub const PEEK_OFF = 42;
-    pub const NOFCS = 43;
-    pub const LOCK_FILTER = 44;
-    pub const SELECT_ERR_QUEUE = 45;
-    pub const BUSY_POLL = 46;
-    pub const MAX_PACING_RATE = 47;
-    pub const BPF_EXTENSIONS = 48;
-    pub const INCOMING_CPU = 49;
-    pub const ATTACH_BPF = 50;
-    pub const DETACH_BPF = DETACH_FILTER;
-    pub const ATTACH_REUSEPORT_CBPF = 51;
-    pub const ATTACH_REUSEPORT_EBPF = 52;
-    pub const CNX_ADVICE = 53;
-    pub const MEMINFO = 55;
-    pub const INCOMING_NAPI_ID = 56;
-    pub const COOKIE = 57;
-    pub const PEERGROUPS = 59;
-    pub const ZEROCOPY = 60;
-    pub const TXTIME = 61;
-    pub const BINDTOIFINDEX = 62;
-    pub const TIMESTAMP_NEW = 63;
-    pub const TIMESTAMPNS_NEW = 64;
-    pub const TIMESTAMPING_NEW = 65;
-    pub const RCVTIMEO_NEW = 66;
-    pub const SNDTIMEO_NEW = 67;
-    pub const DETACH_REUSEPORT_BPF = 68;
-} else if (is_ppc or is_ppc64) struct {
-    pub const DEBUG = 1;
-    pub const REUSEADDR = 2;
-    pub const TYPE = 3;
-    pub const ERROR = 4;
-    pub const DONTROUTE = 5;
-    pub const BROADCAST = 6;
-    pub const SNDBUF = 7;
-    pub const RCVBUF = 8;
-    pub const KEEPALIVE = 9;
-    pub const OOBINLINE = 10;
-    pub const NO_CHECK = 11;
-    pub const PRIORITY = 12;
-    pub const LINGER = 13;
-    pub const BSDCOMPAT = 14;
-    pub const REUSEPORT = 15;
-    pub const RCVLOWAT = 16;
-    pub const SNDLOWAT = 17;
-    pub const RCVTIMEO = 18;
-    pub const SNDTIMEO = 19;
-    pub const PASSCRED = 20;
-    pub const PEERCRED = 21;
-    pub const ACCEPTCONN = 30;
-    pub const PEERSEC = 31;
-    pub const SNDBUFFORCE = 32;
-    pub const RCVBUFFORCE = 33;
-    pub const PROTOCOL = 38;
-    pub const DOMAIN = 39;
-
-    pub const SECURITY_AUTHENTICATION = 22;
-    pub const SECURITY_ENCRYPTION_TRANSPORT = 23;
-    pub const SECURITY_ENCRYPTION_NETWORK = 24;
-
-    pub const BINDTODEVICE = 25;
-
-    pub const ATTACH_FILTER = 26;
-    pub const DETACH_FILTER = 27;
-    pub const GET_FILTER = ATTACH_FILTER;
-
-    pub const PEERNAME = 28;
-    pub const TIMESTAMP_OLD = 29;
-    pub const PASSSEC = 34;
-    pub const TIMESTAMPNS_OLD = 35;
-    pub const MARK = 36;
-    pub const TIMESTAMPING_OLD = 37;
-
-    pub const RXQ_OVFL = 40;
-    pub const WIFI_STATUS = 41;
-    pub const PEEK_OFF = 42;
-    pub const NOFCS = 43;
-    pub const LOCK_FILTER = 44;
-    pub const SELECT_ERR_QUEUE = 45;
-    pub const BUSY_POLL = 46;
-    pub const MAX_PACING_RATE = 47;
-    pub const BPF_EXTENSIONS = 48;
-    pub const INCOMING_CPU = 49;
-    pub const ATTACH_BPF = 50;
-    pub const DETACH_BPF = DETACH_FILTER;
-    pub const ATTACH_REUSEPORT_CBPF = 51;
-    pub const ATTACH_REUSEPORT_EBPF = 52;
-    pub const CNX_ADVICE = 53;
-    pub const MEMINFO = 55;
-    pub const INCOMING_NAPI_ID = 56;
-    pub const COOKIE = 57;
-    pub const PEERGROUPS = 59;
-    pub const ZEROCOPY = 60;
-    pub const TXTIME = 61;
-    pub const BINDTOIFINDEX = 62;
-    pub const TIMESTAMP_NEW = 63;
-    pub const TIMESTAMPNS_NEW = 64;
-    pub const TIMESTAMPING_NEW = 65;
-    pub const RCVTIMEO_NEW = 66;
-    pub const SNDTIMEO_NEW = 67;
-    pub const DETACH_REUSEPORT_BPF = 68;
-} else struct {
-    pub const DEBUG = 1;
-    pub const REUSEADDR = 2;
-    pub const TYPE = 3;
-    pub const ERROR = 4;
-    pub const DONTROUTE = 5;
-    pub const BROADCAST = 6;
-    pub const SNDBUF = 7;
-    pub const RCVBUF = 8;
-    pub const KEEPALIVE = 9;
-    pub const OOBINLINE = 10;
-    pub const NO_CHECK = 11;
-    pub const PRIORITY = 12;
-    pub const LINGER = 13;
-    pub const BSDCOMPAT = 14;
-    pub const REUSEPORT = 15;
-    pub const PASSCRED = 16;
-    pub const PEERCRED = 17;
-    pub const RCVLOWAT = 18;
-    pub const SNDLOWAT = 19;
-    pub const RCVTIMEO = 20;
-    pub const SNDTIMEO = 21;
-    pub const ACCEPTCONN = 30;
-    pub const PEERSEC = 31;
-    pub const SNDBUFFORCE = 32;
-    pub const RCVBUFFORCE = 33;
-    pub const PROTOCOL = 38;
-    pub const DOMAIN = 39;
+pub const SO = struct {
+    pub usingnamespace if (is_mips) struct {
+        pub const DEBUG = 1;
+        pub const REUSEADDR = 0x0004;
+        pub const KEEPALIVE = 0x0008;
+        pub const DONTROUTE = 0x0010;
+        pub const BROADCAST = 0x0020;
+        pub const LINGER = 0x0080;
+        pub const OOBINLINE = 0x0100;
+        pub const REUSEPORT = 0x0200;
+        pub const SNDBUF = 0x1001;
+        pub const RCVBUF = 0x1002;
+        pub const SNDLOWAT = 0x1003;
+        pub const RCVLOWAT = 0x1004;
+        pub const RCVTIMEO = 0x1006;
+        pub const SNDTIMEO = 0x1005;
+        pub const ERROR = 0x1007;
+        pub const TYPE = 0x1008;
+        pub const ACCEPTCONN = 0x1009;
+        pub const PROTOCOL = 0x1028;
+        pub const DOMAIN = 0x1029;
+        pub const NO_CHECK = 11;
+        pub const PRIORITY = 12;
+        pub const BSDCOMPAT = 14;
+        pub const PASSCRED = 17;
+        pub const PEERCRED = 18;
+        pub const PEERSEC = 30;
+        pub const SNDBUFFORCE = 31;
+        pub const RCVBUFFORCE = 33;
+    } else if (is_ppc or is_ppc64) struct {
+        pub const DEBUG = 1;
+        pub const REUSEADDR = 2;
+        pub const TYPE = 3;
+        pub const ERROR = 4;
+        pub const DONTROUTE = 5;
+        pub const BROADCAST = 6;
+        pub const SNDBUF = 7;
+        pub const RCVBUF = 8;
+        pub const KEEPALIVE = 9;
+        pub const OOBINLINE = 10;
+        pub const NO_CHECK = 11;
+        pub const PRIORITY = 12;
+        pub const LINGER = 13;
+        pub const BSDCOMPAT = 14;
+        pub const REUSEPORT = 15;
+        pub const RCVLOWAT = 16;
+        pub const SNDLOWAT = 17;
+        pub const RCVTIMEO = 18;
+        pub const SNDTIMEO = 19;
+        pub const PASSCRED = 20;
+        pub const PEERCRED = 21;
+        pub const ACCEPTCONN = 30;
+        pub const PEERSEC = 31;
+        pub const SNDBUFFORCE = 32;
+        pub const RCVBUFFORCE = 33;
+        pub const PROTOCOL = 38;
+        pub const DOMAIN = 39;
+    } else struct {
+        pub const DEBUG = 1;
+        pub const REUSEADDR = 2;
+        pub const TYPE = 3;
+        pub const ERROR = 4;
+        pub const DONTROUTE = 5;
+        pub const BROADCAST = 6;
+        pub const SNDBUF = 7;
+        pub const RCVBUF = 8;
+        pub const KEEPALIVE = 9;
+        pub const OOBINLINE = 10;
+        pub const NO_CHECK = 11;
+        pub const PRIORITY = 12;
+        pub const LINGER = 13;
+        pub const BSDCOMPAT = 14;
+        pub const REUSEPORT = 15;
+        pub const PASSCRED = 16;
+        pub const PEERCRED = 17;
+        pub const RCVLOWAT = 18;
+        pub const SNDLOWAT = 19;
+        pub const RCVTIMEO = 20;
+        pub const SNDTIMEO = 21;
+        pub const ACCEPTCONN = 30;
+        pub const PEERSEC = 31;
+        pub const SNDBUFFORCE = 32;
+        pub const RCVBUFFORCE = 33;
+        pub const PROTOCOL = 38;
+        pub const DOMAIN = 39;
+    };
 
     pub const SECURITY_AUTHENTICATION = 22;
     pub const SECURITY_ENCRYPTION_TRANSPORT = 23;
diff --git a/lib/std/os/linux/mips.zig b/lib/std/os/linux/mips.zig
index 427a1aa6c6..2cc5ed9eeb 100644
--- a/lib/std/os/linux/mips.zig
+++ b/lib/std/os/linux/mips.zig
@@ -696,36 +696,6 @@ pub const MAP = struct {
     pub const @"32BIT" = 0x40;
 };
 
-pub const SO = struct {
-    pub const DEBUG = 1;
-    pub const REUSEADDR = 0x0004;
-    pub const KEEPALIVE = 0x0008;
-    pub const DONTROUTE = 0x0010;
-    pub const BROADCAST = 0x0020;
-    pub const LINGER = 0x0080;
-    pub const OOBINLINE = 0x0100;
-    pub const REUSEPORT = 0x0200;
-    pub const SNDBUF = 0x1001;
-    pub const RCVBUF = 0x1002;
-    pub const SNDLOWAT = 0x1003;
-    pub const RCVLOWAT = 0x1004;
-    pub const RCVTIMEO = 0x1006;
-    pub const SNDTIMEO = 0x1005;
-    pub const ERROR = 0x1007;
-    pub const TYPE = 0x1008;
-    pub const ACCEPTCONN = 0x1009;
-    pub const PROTOCOL = 0x1028;
-    pub const DOMAIN = 0x1029;
-    pub const NO_CHECK = 11;
-    pub const PRIORITY = 12;
-    pub const BSDCOMPAT = 14;
-    pub const PASSCRED = 17;
-    pub const PEERCRED = 18;
-    pub const PEERSEC = 30;
-    pub const SNDBUFFORCE = 31;
-    pub const RCVBUFFORCE = 33;
-};
-
 pub const VDSO = struct {
     pub const CGT_SYM = "__kernel_clock_gettime";
     pub const CGT_VER = "LINUX_2.6.39";
diff --git a/lib/std/os/wasi.zig b/lib/std/os/wasi.zig
index 7cd0206402..029deca3fd 100644
--- a/lib/std/os/wasi.zig
+++ b/lib/std/os/wasi.zig
@@ -292,7 +292,7 @@ pub const EVENTTYPE_FD_WRITE: eventtype_t = 2;
 
 pub const exitcode_t = u32;
 
-pub const fd_t = u32;
+pub const fd_t = i32;
 
 pub const fdflags_t = u16;
 pub const FDFLAG = struct {
@@ -461,8 +461,10 @@ pub const RIGHT = struct {
 };
 
 pub const sdflags_t = u8;
-pub const SHUT_RD: sdflags_t = 0x01;
-pub const SHUT_WR: sdflags_t = 0x02;
+pub const SHUT = struct {
+    pub const RD: sdflags_t = 0x01;
+    pub const WR: sdflags_t = 0x02;
+};
 
 pub const siflags_t = u16;
 
diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index 82ee089970..9fd125a775 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -243,9 +243,9 @@ pub fn addCases(ctx: *TestContext) !void {
 
     ctx.objErrStage1("array in c exported function",
         \\export fn zig_array(x: [10]u8) void {
-        \\try expect(std.mem.eql(u8, &x, "1234567890"));
+        \\    try std.testing.expect(std.mem.eql(u8, &x, "1234567890"));
         \\}
-        \\
+        \\const std = @import("std");
         \\export fn zig_return_array() [10]u8 {
         \\    return "1234567890".*;
         \\}
@@ -2787,6 +2787,7 @@ pub fn addCases(ctx: *TestContext) !void {
         \\    _ = msg; _ = error_return_trace;
         \\    while (true) {}
         \\}
+        \\const builtin = @import("std").builtin;
     , &[_][]const u8{
         "error: expected type 'fn([]const u8, ?*std.builtin.StackTrace) noreturn', found 'fn([]const u8,anytype) anytype'",
         "note: only one of the functions is generic",
@@ -2832,6 +2833,7 @@ pub fn addCases(ctx: *TestContext) !void {
         \\    var s: Foo = Foo.E;
         \\    _ = s;
         \\}
+        \\const D = 1;
     , &[_][]const u8{
         "tmp.zig:1:17: error: enum 'Foo' depends on itself",
     });