Example:
	//go:cgo_ldflag "-lpthread"
	//go:cgo_ldflag "-L/usr/local/sqlite3/lib"

A package compiled with cgo will include directives for both
internal and external linking; the linker will select the appropriate
subset for the chosen linking mode.

Example

As a simple example, consider a package that uses cgo to call C.sin.
The following code will be generated by cgo:

	// compiled by gc

	//go:cgo_ldflag "-lm"

		r, size := utf8.DecodeRuneInString(s[i:])
		i += size
		// Officially, ZIP uses CP-437, but many readers use the system's
		// local character encoding. Most encoding are compatible with a large
		// subset of CP-437, which itself is ASCII-like.
		//
		// Forbid 0x7e and 0x5c since EUC-KR and Shift-JIS replace those
		// characters with localized currency and overline characters.
		if r < 0x20 || r > 0x7d || r == 0x5c {

observes a synchronizing write-like memory operation <i>w</i>
(that is, if <i>W</i>(<i>r</i>) = <i>w</i>),
then <i>w</i> is synchronized before <i>r</i>.
Informally, the synchronized before relation is a subset of the implied total order
mentioned in the previous paragraph,
limited to the information that <i>W</i> directly observes.
</p>

<p>
The <i>happens before</i> relation is defined as the transitive closure of the