breaking API changes to all readInt/writeInt functions & more

 * add `@bswap` builtin function. See #767
 * comptime evaluation facilities are improved to be able to
   handle a `@ptrCast` with a backing array.
 * `@truncate` allows "truncating" a u0 value to any integer
   type, and the result is always comptime known to be `0`.
 * when specifying pointer alignment in a type expression,
   the alignment value of pointers which do not have addresses
   at runtime is ignored, and always has the default/ABI alignment
 * threw in a fix to freebsd/x86_64.zig to update syntax from
   language changes
 * some improvements are pending #863

closes #638
closes #1733

std lib API changes
 * io.InStream().readIntNe renamed to readIntNative
 * io.InStream().readIntLe renamed to readIntLittle
 * io.InStream().readIntBe renamed to readIntBig
 * introduced io.InStream().readIntForeign
 * io.InStream().readInt has parameter order changed
 * io.InStream().readVarInt has parameter order changed
 * io.InStream().writeIntNe renamed to writeIntNative
 * introduced io.InStream().writeIntForeign
 * io.InStream().writeIntLe renamed to writeIntLittle
 * io.InStream().writeIntBe renamed to writeIntBig
 * io.InStream().writeInt has parameter order changed
 * mem.readInt has different parameters and semantics
 * introduced mem.readIntNative
 * introduced mem.readIntForeign
 * mem.readIntBE renamed to mem.readIntBig and different API
 * mem.readIntLE renamed to mem.readIntLittle and different API
 * introduced mem.readIntSliceNative
 * introduced mem.readIntSliceForeign
 * introduced mem.readIntSliceLittle
 * introduced mem.readIntSliceBig
 * introduced mem.readIntSlice
 * mem.writeInt has different parameters and semantics
 * introduced mem.writeIntNative
 * introduced mem.writeIntForeign
 * mem.writeIntBE renamed to mem.readIntBig and different semantics
 * mem.writeIntLE renamed to mem.readIntLittle and different semantics
 * introduced mem.writeIntSliceForeign
 * introduced mem.writeIntSliceNative
 * introduced mem.writeIntSliceBig
 * introduced mem.writeIntSliceLittle
 * introduced mem.writeIntSlice
 * removed mem.endianSwapIfLe
 * removed mem.endianSwapIfBe
 * removed mem.endianSwapIf
 * added mem.littleToNative
 * added mem.bigToNative
 * added mem.toNative
 * added mem.nativeTo
 * added mem.nativeToLittle
 * added mem.nativeToBig

1 files changed, 12 insertions, 0 deletions

diff --git a/test/compile_errors.zig b/test/compile_errors.zig
index be839f0550..ee3741ee6b 100644
--- a/test/compile_errors.zig
+++ b/test/compile_errors.zig
@@ -2,6 +2,18 @@ const tests = @import("tests.zig");
 
 pub fn addCases(cases: *tests.CompileErrorContext) void {
     cases.add(
+        "reading past end of pointer casted array",
+        \\comptime {
+        \\    const array = "aoeu";
+        \\    const slice = array[2..];
+        \\    const int_ptr = @ptrCast(*const u24, slice.ptr);
+        \\    const deref = int_ptr.*;
+        \\}
+    ,
+        ".tmp_source.zig:5:26: error: attempt to read 3 bytes from [4]u8 at index 2 which is 2 bytes",
+    );
+
+    cases.add(
         "error note for function parameter incompatibility",
         \\fn do_the_thing(func: fn (arg: i32) void) void {}
         \\fn bar(arg: bool) void {}