Support the clang toolchain when link time optimization is configured. Please note that this is NOT intended to enable lto by default and NOT to fix all possible clang-supporting builds or test issues .
It works on my Linux x86_64 SUSE 15 test machine with clang15.0.7, also on macOS with Xcode 13.1 devkit and Xcode 15.4 . To be able to build on macOS with Xcode, I had to deal with one issue. The lto-link process runs into this error ld: <inline asm>:11:1: symbol 'SpinPause_return' is already defined SpinPause_return: ^ for architecture arm64 clang: error: linker command failed with exit code 1 (use -v to see invocation) Seems that when building with LTO, the inline assembler code in SpinPause() is not handled well. In the lto inlining the label SpinPause_return is generated multiple times and causes an 'already defined' error. This goes away when adding NOINLINE to this function. Linux/clang did not show this issue, probably the toolchain there does not have the error. ------------- Commit messages: - JDK-8344607 Changes: https://git.openjdk.org/jdk/pull/22412/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22412&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8344607 Stats: 5 lines in 2 files changed: 5 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/22412.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/22412/head:pull/22412 PR: https://git.openjdk.org/jdk/pull/22412
