"PK\x01\x02\x14\x00\x14\x00\b\b\b\x004\x9d3?Ļ\x14\xe3\xd8\x01\x00\x00\xd8\x03\x00\x00 \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00:E\x02\x00res/layout/wallpaper_cropper.xml",

Go <code>const</code> declarations defined in the current package.
Go assembly should avoid making assumptions about the layout of Go
types and instead use these constants.
This improves the readability of assembly code, and keeps it robust to
changes in data layout either in the Go type definitions or in the
layout rules used by the Go compiler.
</p>

<p>
Constants are of the form <code>const_<i>name</i></code>.

---
title: "Go, Backwards Compatibility, and GODEBUG"
layout: article
---

<!--
This document is kept in the Go repo, not x/website,
because it documents the full list of known GODEBUG settings,
which are tied to a specific release.
-->

## Introduction {#intro}

Go's emphasis on backwards compatibility is one of its key strengths.
There are, however, times when we cannot maintain complete compatibility.

	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>
	A call to the built-in function
	<a href="#Handling_panics"><code>panic</code></a>.
	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>
	A <a href="#Blocks">block</a> in which the statement list ends in a terminating statement.
	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>

together. The directive can include a list of build constraints limiting its
effect to systems satisfying one of the constraints
(see https://golang.org/pkg/go/build/#hdr-Build_Constraints for details about the constraint syntax).
For example:

	// #cgo CFLAGS: -DPNG_DEBUG=1
	// #cgo amd64 386 CFLAGS: -DX86=1
	// #cgo LDFLAGS: -lpng
	// #include <png.h>
	import "C"

			output = output[1:]
			continue
		}
		t.Errorf("unexpected output: %q", output[0])
		output = output[1:]
	}

	// Checked printing.
	// Now check machine code layout.

	top := pList.Firstpc
	var text *obj.LSym
	ok = true
	ctxt.DiagFunc = func(format string, args ...interface{}) {
		t.Errorf(format, args...)
		ok = false
	}
	obj.Flushplist(ctxt, pList, nil)

	// Make sure that the input format is GNU.
	// Unfortunately, the STAR format also has a sparse header format that uses
	// the same type flag but has a completely different layout.
	if blk.getFormat() != FormatGNU {
		return nil, ErrHeader
	}
	hdr.Format.mayOnlyBe(FormatGNU)

	var p parser
	hdr.Size = p.parseNumeric(blk.toGNU().realSize())
	if p.err != nil {
		return nil, p.err

	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>
	A call to the built-in function
	<a href="#Handling_panics"><code>panic</code></a>.
	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>
	A <a href="#Blocks">block</a> in which the statement list ends in a terminating statement.
	<!-- ul below only for regular layout -->
	<ul> </ul>
</li>

<li>

		}
	}
}

func TestIndexNearPageBoundary(t *testing.T) {
	t.Parallel()
	q := dangerousSlice(t)
	if len(q) > 64 {
		// Only worry about when we're near the end of a page.
		q = q[len(q)-64:]
	}
	b := dangerousSlice(t)
	if len(b) > 256 {
		// Only worry about when we're near the end of a page.
		b = b[len(b)-256:]
	}
	for j := 1; j < len(q); j++ {
		q[j-1] = 1 // difference is only found on the last byte

blank_issues_enabled: true
contact_links:
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    about: Please use one of the forums for questions or general discussions