Defect Report #050
Submission Date: 24 Feb 93
Submittor: Project Editor (P.J. Plauger)
Source: C. Breeus
Subclause 18.104.22.168 says that the type of a wide character constant
is wchar_t, and subclause 6.1.4 says the type of a wide character
string is array of wchar_t.
Subclause 7.1.6 says the typedef name wchar_t must be defined
Question: When a compiler sees a literal of the form L'...'
or L"..." must it not check that
And then, take that integral type as the meaning of wchar_t.
I suppose it cannot just hope for the best and take a type that makes
it feel good.
- The name wchar_t is visible at that place.
- The name is a typedef name. It could be redefined in an inner
- It is a typedef for an integral type. Again, it could be redefined.
A similar issue was explained in response to Defect Report #017 Question
7, regarding size_t. The relevant citation here is from subclause
22.214.171.124, page 29, lines 36-37:
A wide character constant has type wchar_t, an integral
type defined in the <stddef.h> header.
The intent of this sentence is to note that a wide character constant
has an integral type. That integral type is the same integral type
used to define wchar_t in the header <stddef.h>. The sentence
imposes no requirement that this particular definition of wchar_t
be in scope wherever you write a wide character constant. It certainly
does not suggest that the translator should honor any other definition
of wchar_t that may be in scope, as the type for a wide character
Rather, the sentence suggests that the translator knows what integral
type to assign to a wide character constant. The implementation further
knows to define wchar_t within the header <stddef.h> as
having that same integral type. Thus, the program has a way of obtaining
a name for this type, if it chooses - by including the header
<stddef.h>. But it need not invoke that mechanism just to assist
It is an unfortunate, but widespread, practice within the C Standard
to use abbreviated language for describing some types. Thus, subclause
6.1.4, page 31, lines 5-6 say:
for wide string literals, the array elements have type wchar_t,
instead of the more long winded (but clearer):
for wide string literals, the array elements have the same type
used to define wchar_t in the header <stddef.h>, ...
We feel the usage is sufficiently uniform that the meaning intended
by the Committee is sufficiently clear, even as we acknowledge that
the words can be (and have been) misread.
So to put the matter crassly, the translator does ``just
hope for the best and take a type that makes it feel good,'' as
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