291861 - XPCDispInterface.cpp fails to compile with Microsoft Visual Studio 2005 Beta 2

Status: RESOLVED FIXED

(Core :: XPConnect, defect)

Description

[Stephen Walker]

c:/Mozilla/mozilla/js/src/xpconnect/src/XPCDispInterface.cpp(183) : error C2664:
'JS_InternUCStringN' : cannot convert parameter 2 from 'BST
R' to 'const jschar *'
        Types pointed to are unrelated; conversion requires reinterpret_cast,
C-style cast or function-style cast

Comment 1

[Bernard Alleysson]

I think that the real fix would be to change jschar definition in
js\src\jspubtd.h to: "typedef wchar_t   jschar;" (same as PRUnichar definition)

If it is not possible to change the definition then just cast to (const jschar *) ?

Comment 2

[Mike Shaver (:shaver emeritus)]

We should NS_STATIC_CAST here, just as we do elsewhere.

Comment 3

[Brendan Eich [:brendan]]

Re: comment 2: absolutely not, jschar is uint16 per ECMA-262 Edition 3.

/be

Comment 4

[Mike Shaver (:shaver emeritus)]

Brendan meant the wchar_t change at comment 1; he has trouble with numbers
sometimes.

Comment 5

[Stephen Walker]

Attachment: Cast until it compiles

Comment 6

[Bernard Alleysson]

I think that the cast in XPCDispTypeInfo.cpp should be:
-    mName = nsString(chars, len);
+    mName = nsString(NS_REINTERPRET_CAST(const PRUnichar *, chars), len);

About all those casts, I think that it's because of this compiler change:
(from http://msdn2.microsoft.com/library/ms177253(en-us,vs.80).aspx)

/Zc:wchar_t now on by default

    This is Standard C++ behavior: A wchar_t variable will default to the built
in type instead of a short unsigned integer. This change will break binary
compatibility when client code is linked with libraries that were compiled
without /Zc:wchar_t. Use /Zc:wchar_t- to revert to the old, non-standard
behavior. This change was introduced to create conformant code by default.

I don't really understand the binary compatibility problem, though...

See also, fwiw, this can break things:

/Zc:forScope now on by default
    This is Standard C++ behavior: Code that depends on the use of a variable
declared in a for loop after the for loop scope has ended will now fail to
compile. Use /Zc:forScope- to revert to the old, non-standard behavior. This
change was introduced to create conformant code by default.

Comment 7

[Mike Shaver (:shaver emeritus)]

Comment on attachment 182649 [details] [diff] [review]
Cast until it compiles

r+a again, more compiler fixes.

Comment 8

[Stephen Walker]

Attachment: Cast to const PRUnichar * instead

Comment 9

[Mike Shaver (:shaver emeritus)]

Comment on attachment 182656 [details] [diff] [review]
Cast to const PRUnichar * instead

Yeah, that's better.  Thanks for checking in, r+a.

Comment 10

[Stephen Walker]

checked in by db48x