On Tue, 3 Dec 2024 16:46:04 GMT, Matthias Baesken <mbaes...@openjdk.org> wrote:
>> 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. > > Matthias Baesken has updated the pull request incrementally with one > additional commit since the last revision: > > use fat lto objects on AIX/clang Thanks for the reviews ! With the current commit I was able to build with clang and lto enabled on macOS aarch64, AIX and Linux x86_64. (on Linux ppc64le, the whole clang build still fails, but this is a separate issue and it fails also without lto, see https://bugs.openjdk.org/browse/JDK-8338303 8338303: Linux ppc64le with toolchain clang - detection failure in early JVM startup ) ------------- PR Comment: https://git.openjdk.org/jdk/pull/22412#issuecomment-2520613177
