RFR: 8259288: Debug build failure with clang-10 due to -Wimplicit-int-float-conversion

[Hao Sun]

Making the conversion explicit would fix it.

Flag '-Wimplicit-int-float-conversion' is first introduced in clang-10.
Therefore clang-8 and clang-9 are not affected. The flag with similar
functionality in gcc is '-Wfloat-conversion', but it is not enabled by
'-Wall' or '-Wextra'. That's why this warning does not appear when
building with gcc.


Note that we have tested with this patch, debug build succeeded with clang-10 on Linux X86-64/AArch64 machines.
Note that '--with-extra-cxxflags=-Wno-deprecated-copy' should be added when configuration. It's another issue (See JDK-8258010)

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Commit messages:
 - 8259288: Debug build failure with clang-10 due to -Wimplicit-int-float-conversion

Changes: https://git.openjdk.java.net/jdk/pull/1956/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1956&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8259288
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1956.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1956/head:pull/1956

PR: https://git.openjdk.java.net/jdk/pull/1956