diff --git a/lib/c.zig b/lib/c.zig
index 8581ec4e14..e55b8443d9 100644
--- a/lib/c.zig
+++ b/lib/c.zig
@@ -153,7 +153,11 @@ test "strncat" {
 }
 
 fn strcmp(s1: [*:0]const u8, s2: [*:0]const u8) callconv(.C) c_int {
-    return std.cstr.cmp(s1, s2);
+    return switch (std.mem.orderZ(u8, s1, s2)) {
+        .lt => -1,
+        .eq => 0,
+        .gt => 1,
+    };
 }
 
 fn strlen(s: [*:0]const u8) callconv(.C) usize {
diff --git a/lib/std/child_process.zig b/lib/std/child_process.zig
index 9f4d75084f..c0aeba00de 100644
--- a/lib/std/child_process.zig
+++ b/lib/std/child_process.zig
@@ -1,6 +1,5 @@
 const std = @import("std.zig");
 const builtin = @import("builtin");
-const cstr = std.cstr;
 const unicode = std.unicode;
 const io = std.io;
 const fs = std.fs;
diff --git a/lib/std/cstr.zig b/lib/std/cstr.zig
index 0888edf10d..83c6c12a87 100644
--- a/lib/std/cstr.zig
+++ b/lib/std/cstr.zig
@@ -1,100 +1,3 @@
-const std = @import("std.zig");
-const builtin = @import("builtin");
-const debug = std.debug;
-const mem = std.mem;
-const testing = std.testing;
-
-pub const line_sep = switch (builtin.os.tag) {
-    .windows => "\r\n",
-    else => "\n",
-};
-
-pub fn cmp(a: [*:0]const u8, b: [*:0]const u8) i8 {
-    var index: usize = 0;
-    while (a[index] == b[index] and a[index] != 0) : (index += 1) {}
-    if (a[index] > b[index]) {
-        return 1;
-    } else if (a[index] < b[index]) {
-        return -1;
-    } else {
-        return 0;
-    }
-}
-
-test "cstr fns" {
-    try comptime testCStrFnsImpl();
-    try testCStrFnsImpl();
-}
-
-fn testCStrFnsImpl() !void {
-    try testing.expect(cmp("aoeu", "aoez") == -1);
-}
-
-/// Returns a mutable, null-terminated slice with the same length as `slice`.
-/// Caller owns the returned memory.
-pub fn addNullByte(allocator: mem.Allocator, slice: []const u8) ![:0]u8 {
-    const result = try allocator.alloc(u8, slice.len + 1);
-    @memcpy(result[0..slice.len], slice);
-    result[slice.len] = 0;
-    return result[0..slice.len :0];
-}
-
-test "addNullByte" {
-    const slice = try addNullByte(std.testing.allocator, "hello"[0..4]);
-    defer std.testing.allocator.free(slice);
-    try testing.expect(slice.len == 4);
-    try testing.expect(slice[4] == 0);
-}
-
-pub const NullTerminated2DArray = struct {
-    allocator: mem.Allocator,
-    byte_count: usize,
-    ptr: ?[*:null]?[*:0]u8,
-
-    /// Takes N lists of strings, concatenates the lists together, and adds a null terminator
-    /// Caller must deinit result
-    pub fn fromSlices(allocator: mem.Allocator, slices: []const []const []const u8) !NullTerminated2DArray {
-        var new_len: usize = 1; // 1 for the list null
-        var byte_count: usize = 0;
-        for (slices) |slice| {
-            new_len += slice.len;
-            for (slice) |inner| {
-                byte_count += inner.len;
-            }
-            byte_count += slice.len; // for the null terminators of inner
-        }
-
-        const index_size = @sizeOf(usize) * new_len; // size of the ptrs
-        byte_count += index_size;
-
-        const buf = try allocator.alignedAlloc(u8, @alignOf(?*u8), byte_count);
-        errdefer allocator.free(buf);
-
-        var write_index = index_size;
-        const index_buf = mem.bytesAsSlice(?[*]u8, buf);
-
-        var i: usize = 0;
-        for (slices) |slice| {
-            for (slice) |inner| {
-                index_buf[i] = buf.ptr + write_index;
-                i += 1;
-                @memcpy(buf[write_index..][0..inner.len], inner);
-                write_index += inner.len;
-                buf[write_index] = 0;
-                write_index += 1;
-            }
-        }
-        index_buf[i] = null;
-
-        return NullTerminated2DArray{
-            .allocator = allocator,
-            .byte_count = byte_count,
-            .ptr = @as(?[*:null]?[*:0]u8, @ptrCast(buf.ptr)),
-        };
-    }
-
-    pub fn deinit(self: *NullTerminated2DArray) void {
-        const buf = @as([*]u8, @ptrCast(self.ptr));
-        self.allocator.free(buf[0..self.byte_count]);
-    }
-};
+pub const line_sep = @compileError("deprecated; choose correct end-of-line sequence of characters by yourself instead");
+pub const cmp = @compileError("deprecated; use `std.mem.orderZ` instead");
+pub const addNullByte = @compileError("deprecated; use `allocator.dupeZ(u8, stuff)` instead");
diff --git a/lib/std/mem.zig b/lib/std/mem.zig
index 229bc0b63e..36e9813c2a 100644
--- a/lib/std/mem.zig
+++ b/lib/std/mem.zig
@@ -607,12 +607,24 @@ pub fn order(comptime T: type, lhs: []const T, rhs: []const T) math.Order {
     return math.order(lhs.len, rhs.len);
 }
 
-test "order" {
+/// Compares two many-item pointers with NUL-termination lexicographically.
+pub fn orderZ(comptime T: type, lhs: [*:0]const T, rhs: [*:0]const T) math.Order {
+    var i: usize = 0;
+    while (lhs[i] == rhs[i] and lhs[i] != 0) : (i += 1) {}
+    return math.order(lhs[i], rhs[i]);
+}
+
+test "order and orderZ" {
     try testing.expect(order(u8, "abcd", "bee") == .lt);
+    try testing.expect(orderZ(u8, "abcd", "bee") == .lt);
     try testing.expect(order(u8, "abc", "abc") == .eq);
+    try testing.expect(orderZ(u8, "abc", "abc") == .eq);
     try testing.expect(order(u8, "abc", "abc0") == .lt);
+    try testing.expect(orderZ(u8, "abc", "abc0") == .lt);
     try testing.expect(order(u8, "", "") == .eq);
+    try testing.expect(orderZ(u8, "", "") == .eq);
     try testing.expect(order(u8, "", "a") == .lt);
+    try testing.expect(orderZ(u8, "", "a") == .lt);
 }
 
 /// Returns true if lhs < rhs, false otherwise
diff --git a/lib/std/net.zig b/lib/std/net.zig
index af291f6414..7a8ca62022 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -783,7 +783,7 @@ pub fn getAddressList(allocator: mem.Allocator, name: []const u8, port: u16) Get
     errdefer result.deinit();
 
     if (builtin.target.os.tag == .windows) {
-        const name_c = try std.cstr.addNullByte(allocator, name);
+        const name_c = try allocator.dupeZ(u8, name);
         defer allocator.free(name_c);
 
         const port_c = try std.fmt.allocPrintZ(allocator, "{}", .{port});
@@ -855,7 +855,7 @@ pub fn getAddressList(allocator: mem.Allocator, name: []const u8, port: u16) Get
     }
 
     if (builtin.link_libc) {
-        const name_c = try std.cstr.addNullByte(allocator, name);
+        const name_c = try allocator.dupeZ(u8, name);
         defer allocator.free(name_c);
 
         const port_c = try std.fmt.allocPrintZ(allocator, "{}", .{port});
diff --git a/lib/std/zig/c_builtins.zig b/lib/std/zig/c_builtins.zig
index 7f0414c96f..46d376a437 100644
--- a/lib/std/zig/c_builtins.zig
+++ b/lib/std/zig/c_builtins.zig
@@ -126,7 +126,11 @@ pub inline fn __builtin_strlen(s: [*c]const u8) usize {
     return std.mem.sliceTo(s, 0).len;
 }
 pub inline fn __builtin_strcmp(s1: [*c]const u8, s2: [*c]const u8) c_int {
-    return @as(c_int, std.cstr.cmp(s1, s2));
+    return switch (std.mem.orderZ(u8, s1, s2)) {
+        .lt => -1,
+        .eq => 0,
+        .gt => 1,
+    };
 }
 
 pub inline fn __builtin_object_size(ptr: ?*const anyopaque, ty: c_int) usize {
diff --git a/src/Compilation.zig b/src/Compilation.zig
index 902586bf7a..92de342a16 100644
--- a/src/Compilation.zig
+++ b/src/Compilation.zig
@@ -5066,7 +5066,7 @@ fn parseLldStderr(comp: *Compilation, comptime prefix: []const u8, stderr: []con
     defer context_lines.deinit();
 
     var current_err: ?*LldError = null;
-    var lines = mem.splitSequence(u8, stderr, std.cstr.line_sep);
+    var lines = mem.splitSequence(u8, stderr, if (builtin.os.tag == .windows) "\r\n" else "\n");
     while (lines.next()) |line| {
         if (mem.startsWith(u8, line, prefix ++ ":")) {
             if (current_err) |err| {
diff --git a/src/codegen/c/type.zig b/src/codegen/c/type.zig
index efff2e557c..dbdb65ac29 100644
--- a/src/codegen/c/type.zig
+++ b/src/codegen/c/type.zig
@@ -1,5 +1,4 @@
 const std = @import("std");
-const cstr = std.cstr;
 const mem = std.mem;
 const Allocator = mem.Allocator;
 const assert = std.debug.assert;
@@ -1025,7 +1024,7 @@ pub const CType = extern union {
                 for (lhs_data, rhs_data) |lhs_field, rhs_field| {
                     if (!ctx.eqlIndex(lhs_field.type, rhs_field.type)) return false;
                     if (lhs_field.alignas.@"align" != rhs_field.alignas.@"align") return false;
-                    if (cstr.cmp(lhs_field.name, rhs_field.name) != 0) return false;
+                    if (std.mem.orderZ(u8, lhs_field.name, rhs_field.name) != .eq) return false;
                 }
                 return true;
             },
diff --git a/test/behavior/basic.zig b/test/behavior/basic.zig
index 87cbb3e242..57a579cfdb 100644
--- a/test/behavior/basic.zig
+++ b/test/behavior/basic.zig
@@ -647,7 +647,7 @@ test "multiline string literal is null terminated" {
         \\three
     ;
     const s2 = "one\ntwo)\nthree";
-    try expect(std.cstr.cmp(s1, s2) == 0);
+    try expect(std.mem.orderZ(u8, s1, s2) == .eq);
 }
 
 test "string escapes" {
diff --git a/test/cbe.zig b/test/cbe.zig
index b56202c7e5..7eb212b2fe 100644
--- a/test/cbe.zig
+++ b/test/cbe.zig
@@ -1,5 +1,6 @@
 const std = @import("std");
 const Cases = @import("src/Cases.zig");
+const nl = if (@import("builtin").os.tag == .windows) "\r\n" else "\n";
 
 // These tests should work with all platforms, but we're using linux_x64 for
 // now for consistency. Will be expanded eventually.
@@ -19,7 +20,7 @@ pub fn addCases(ctx: *Cases) !void {
             \\    _ = puts("hello world!");
             \\    return 0;
             \\}
-        , "hello world!" ++ std.cstr.line_sep);
+        , "hello world!" ++ nl);
 
         // Now change the message only
         case.addCompareOutput(
@@ -28,7 +29,7 @@ pub fn addCases(ctx: *Cases) !void {
             \\    _ = puts("yo");
             \\    return 0;
             \\}
-        , "yo" ++ std.cstr.line_sep);
+        , "yo" ++ nl);
 
         // Add an unused Decl
         case.addCompareOutput(
@@ -38,7 +39,7 @@ pub fn addCases(ctx: *Cases) !void {
             \\    return 0;
             \\}
             \\fn unused() void {}
-        , "yo!" ++ std.cstr.line_sep);
+        , "yo!" ++ nl);
 
         // Comptime return type and calling convention expected.
         case.addError(
@@ -67,7 +68,7 @@ pub fn addCases(ctx: *Cases) !void {
             \\    _ = printf("Hello, %s!\n", "world");
             \\    return 0;
             \\}
-        , "Hello, world!" ++ std.cstr.line_sep);
+        , "Hello, world!" ++ nl);
     }
 
     {
diff --git a/test/compare_output.zig b/test/compare_output.zig
index 92dfd76b58..bcdc642a1e 100644
--- a/test/compare_output.zig
+++ b/test/compare_output.zig
@@ -15,7 +15,7 @@ pub fn addCases(cases: *tests.CompareOutputContext) void {
         \\    _ = c.puts("Hello, world!");
         \\    return 0;
         \\}
-    , "Hello, world!" ++ std.cstr.line_sep);
+    , "Hello, world!" ++ if (@import("builtin").os.tag == .windows) "\r\n" else "\n");
 
     cases.add("hello world without libc",
         \\const io = @import("std").io;
diff --git a/test/run_translated_c.zig b/test/run_translated_c.zig
index a64a3eb7a4..fe32d376d2 100644
--- a/test/run_translated_c.zig
+++ b/test/run_translated_c.zig
@@ -1,6 +1,6 @@
 const std = @import("std");
 const tests = @import("tests.zig");
-const nl = std.cstr.line_sep;
+const nl = if (@import("builtin").os.tag == .windows) "\r\n" else "\n";
 
 pub fn addCases(cases: *tests.RunTranslatedCContext) void {
     cases.add("dereference address of",