langref: update for language changes

doc/langref.html.in

@@ -2103,8 +2103,9 @@ or
       less than {#syntax#}1 << 29{#endsyntax#}.
       </p>
       <p>
-      In Zig, a pointer type has an alignment value. If the value is equal to the
-      alignment of the underlying type, it can be omitted from the type:
+      Pointer types may explicitly specify an alignment in bytes. If it is not
+      specified, the alignment is assumed to be equal to the alignment of the
+      underlying type.
       </p>
       {#code|test_variable_alignment.zig#}
 

doc/langref/test_comptime_invalid_error_code.zig

@@ -1,8 +1,5 @@
 comptime {
-    const err = error.AnError;
-    const number = @intFromError(err) + 10;
-    const invalid_err = @errorFromInt(number);
-    _ = invalid_err;
+    _ = @errorFromInt(12345);
 }
 
-// test_error=integer value '11' represents no error
+// test_error=integer value '12345' represents no error

doc/langref/test_missized_packed_struct.zig

@@ -3,4 +3,4 @@ test "missized packed struct" {
     _ = S{ .a = 4, .b = 2 };
 }
 
-// test_error=backing integer type 'u32' has bit size 32 but the struct fields have a total bit size of 24
+// test_error=backing integer bit width does not match total bit width of fields

doc/langref/test_variable_alignment.zig

@@ -1,15 +1,20 @@
 const std = @import("std");
 const builtin = @import("builtin");
+const expect = std.testing.expect;
 const expectEqual = std.testing.expectEqual;
 
 test "variable alignment" {
     var x: i32 = 1234;
-    const align_of_i32 = @alignOf(@TypeOf(x));
+
     try expectEqual(*i32, @TypeOf(&x));
-    try expectEqual(*align(align_of_i32) i32, *i32);
-    if (builtin.target.cpu.arch == .x86_64) {
-        try expectEqual(4, @typeInfo(*i32).pointer.alignment);
-    }
+
+    try expect(@intFromPtr(&x) % @alignOf(i32) == 0);
+
+    // The implicitly-aligned pointer can be coerced to be explicitly-aligned to
+    // the alignment of the underlying type `i32`:
+    const ptr: *align(@alignOf(i32)) i32 = &x;
+
+    try expectEqual(1234, ptr.*);
 }
 
 // test