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 (mostly linux/posix specific 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
-------------
Commit messages:
- Rest of the tests
- More test
- AArch64
- Disable for tests
- Fix apostrophe
- Last few manual
- Automatics
- WIP
- More disabled warnings
- Enable narrow conversion warnings
Changes: https://git.openjdk.org/jdk/pull/9516/files
Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9516&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8290373
Stats: 1586 lines in 318 files changed: 1579 ins; 3 del; 4 mod
Patch: https://git.openjdk.org/jdk/pull/9516.diff
Fetch: git fetch https://git.openjdk.org/jdk pull/9516/head:pull/9516
PR: https://git.openjdk.org/jdk/pull/9516
