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
`RANGEBASE` was added by [JDK-6500501](https://bugs.openjdk.java.net/browse/JDK-6500501) and later was modified by [JDK-8027829](https://bugs.openjdk.java.net/browse/JDK-8027829) Note the original comment from 6500501: // The characters allowed in a class or method name. All characters > 0x7f // are allowed in order to handle obfuscated class files (e.g. Volano) ------------- PR: https://git.openjdk.java.net/jdk/pull/5704