On Sun, 26 Sep 2021 09:55:00 GMT, Jie Fu <ji...@openjdk.org> wrote:
> Hi all,
>
> I tried to build OpenJDK on Cygwin (Windows 2016 + VS2019).
> However, I failed with C4474 and C4778 warnings as below:
>
> Compiling 100 properties into resource bundles for java.desktop
> Compiling 3038 files for java.base
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(269): error
> C2220: the following warning is treated as an error
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(269): warning
> C4778: 'sscanf' : unterminated format string
> '%255[*\x01\x02\x03\x04\x05\x06\a\b\n\v\f\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f!"#$%&'*+,-0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ\^_`abcdefghijklmnopqrstuvwxyz{|}~\xe2\x82\xac\xe4\xba\x97\xe5\x84\x8e\xe5\x8e\x97%n'
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(269): warning
> C4474: 'sscanf' : too many arguments passed for format string
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(269): note:
> placeholders and their parameters expect 1 variadic arguments, but 3 were
> provided
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(319): warning
> C4778: 'sscanf' : unterminated format string
> '%1022[[);/\x01\x02\x03\x04\x05\x06\a\b\n\v\f\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f!"#$%&'*+,-0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ\^_`abcdefghijklmnopqrstuvwxyz{|}~\xe2\x82\xac\xe4\xba\x97\xe5\x84\x8e\xe5\x8e%n'
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(319): warning
> C4474: 'sscanf' : too many arguments passed for format string
> e:\jiefu\ws\jdk\src\hotspot\share\compiler\methodMatcher.cpp(319): note:
> placeholders and their parameters expect 0 variadic arguments, but 2 were
> provided
>
>
> The failure is caused by non-ASCII chars in the format string of sscanf
> [1][2], which is non-portable on our Windows platform.
> In fact, these non-ASCII coding also triggers C4819 warning, which had been
> disabled in JDK-8216154 [3].
> And I also found an article showing that sscanf may fail with non-ASCII in
> the format string [4].
>
> So it would be nice to remove these non-ASCII chars (`\x80 ~ \xef`).
> And I think it's safe to do so.
>
> This is because:
> 1) There are actually no non-ASCII chars for package/class/method/signature
> names.
> 2) I don't think there is a use case, in which people will input non-ASCII
> for `CompileCommand`.
>
> You may argue that the non-ASCII may be used by the parser itself.
> But I didn't find that usage at all. (Please let me know if I miss something.)
>
> So I suggest to remove these non-ASCII code to make HotSpot to be more
> portable.
> And if we do so, we can also remove the only one
> `PRAGMA_DISABLE_MSVC_WARNING(4819)` [5].
>
> Testing:
> - Build tests on Windows
> - tier1~3 on Linux/x64
>
> Thanks.
> Best regards,
> Jie
>
> [1]
> https://github.com/openjdk/jdk/blob/master/src/hotspot/share/compiler/methodMatcher.cpp#L269
> [2]
> https://github.com/openjdk/jdk/blob/master/src/hotspot/share/compiler/methodMatcher.cpp#L319
> [3]
> https://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2019-January/032014.html
> [4] https://jeffpar.github.io/kbarchive/kb/047/Q47369/
> [5]
> https://github.com/openjdk/jdk/blob/master/src/hotspot/share/compiler/methodMatcher.cpp#L246
My experiments above with ` -XX:CompileCommand='compileonly,*::爪哇'` was done on
Linux. I tried doing the same on Windows. On US-English Windows, the default
codepage is 437 (DOS Latin US). If I change it to 65001 (UTF8) then Java is
able to output CJK characters to the console.
public class CJK {
public static void main(String args[]) {
System.out.println(args[0]);
\u722a\u54c7();
}
static void \u722a\u54c7() { // Chinese word for "Java"
Thread.dumpStack();
}
}
c:\ade>chcp
Active code page: 437
c:\ade>jdk-17\bin\java -cp . CJK 123
123
java.lang.Exception: Stack trace
at java.base/java.lang.Thread.dumpStack(Thread.java:1380)
at CJK.??(CJK.java:8)
at CJK.main(CJK.java:4)
c:\ade>chcp 65001
Active code page: 65001
c:\ade>jdk-17\bin\java -cp . CJK 爪哇
??
java.lang.Exception: Stack trace
at java.base/java.lang.Thread.dumpStack(Thread.java:1380)
at CJK.爪哇(CJK.java:8)
at CJK.main(CJK.java:4)
As you can see, the CJK characters in the command-line arguments can't even be
correctly passed as arguments to the Java main class. If that doesn't work, I
can't see how we can get `-XX:CompileCommand` to work with CJK characters.
-------------
PR: https://git.openjdk.java.net/jdk/pull/5704
