warnings.dd

Ddoc

$(D_S Warnings,

	$(P Depending on one's point of view, warnings are either a symptom
	of broken language design or a useful $(SINGLEQUOTE lint) like tool to analyze
	code and look for potential trouble spots.
	Most of the time, those trouble spots will be legitimate code
	intended to be that way. More rarely, it may indicate an
	unintentional error on the part of the programmer.
	)

	$(P Warnings are not a defined part of the D Programming Language.
	They exist at the discretion of the compiler vendor, and
	will most likely vary from vendor to vendor.
	All constructs for which an implementation may generate a warning
	message are legal D code.
	)

	$(P These are the warnings generated by the Digital Mars D compiler
	when the $(B -w) switch is thrown. This mode also forces compiler
	to stop if any warning is produced.
	Most have generated some spirited debate as to whether it should
	be a warning, an error, and what the correct way to write D code
	in these situations should be. Since no consensus emerged,
	they appear as optional warnings, with alternatives on how to
	write correct code.
	)









$(H3 warning - statement is not reachable)

	$(P Consider the following code:)

---
int foo(int i)
{
    return i;
    $(B return i + 1;)
}
---

	$(P The second return statement is not reachable, i.e. it is dead
	code. While dead code is poor style in released code, it can
	legitimately
	happen a lot when rapidly trying to isolate down a bug or experiment
	with different bits of code.
	)

	$(P The warning can be resolved by:
	)

	$(OL
	$(LI Commenting out the dead code with /+ ... +/ comments:
---
int foo(int i)
{
    return i;
    /+
        return i + 1;
     +/
}
---
	)

	$(LI Putting the dead code inside a $(D version(none)) conditional:
---
int foo(int i)
{
    return i;
    $(B version (none))
    {
        return i + 1;
    }
}
---
	)

	$(LI Only compile with warnings enabled when doing release builds.
	)
	)

)

Macros:
	TITLE=Warnings
	SUBNAV=$(SUBNAV_ARTICLES)