On Fri, 15 Jul 2022 13:25:57 GMT, Jorn Vernee <jver...@openjdk.org> wrote:
> This patch enables lossy conversion warnings (C4244 [1]) for hotspot on > Windows/MSVC. Instead of fixing all warnings that were produced from this, > I've instead locally disabled the warning in the files that produced > warnings. This allows gradually making progress with cleaning up these > warnings on a per-file basis, instead of trying to fix all of them in one > shot. > > Out of the ~1100 files that make up hotspot on Windows x64 , ~290 have > warnings for them disabled (not counting aarch64 files), which means that > with this patch ~800 files are protected by enabling this warning globally. > > Warnings can be fixed in individual files, or groups of files in followup > patches, and warnings for those files can be enabled. > > I'm working on a patch that does the same for GCC, but it produces warnings > in about 150 more files, so I wanted to gather feedback on this approach > before continuing with that. > > --- > > To disable warnings for a file, in most cases the following prelude is added > after the last `#include` at the start of a file: > > PRAGMA_DIAG_PUSH > PRAGMA_ALLOW_LOSSY_CONVERSIONS > > And then the following is added at the end of the file for cpp files, or > before closing the header guard for hpp files: > > PRAGMA_DIAG_POP > > 1 notable exception are files produced by adlc, which had their code-gen > modified to add these lines instead. There were also 2 files that include > headers in the middle of the file (ostream.cpp & sharedRuntime.cpp), for > which I've added the PRAGMA's after the include block at the start of the > file instead. They only included system headers, for which disabling warnings > doesn't matter any ways. > > [1]: > https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244?view=msvc-170 I thought PRAGMA_DIAG_PUSH/POP are for narrowing the scope of the pragma. So unless we are concatenating .cpp files together, I would think they are not needed for .cpp files if we want to affect the whole file. ------------- PR: https://git.openjdk.org/jdk/pull/9516
