On Wed, 11 Oct 2023 13:36:01 GMT, Andrew Haley <[email protected]> wrote:
>> A bug in GCC causes shared libraries linked with -ffast-math to disable >> denormal arithmetic. This breaks Java's floating-point semantics. >> >> The bug is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55522 >> >> One solution is to save and restore the floating-point control word around >> System.loadLibrary(). This isn't perfect, because some shared library might >> load another shared library at runtime, but it's a lot better than what we >> do now. >> >> However, this fix is not complete. `dlopen()` is called from many places in >> the JDK. I guess the best thing to do is find and wrap them all. I'd like to >> hear people's opinions. > > Andrew Haley has updated the pull request with a new target base due to a > merge or a rebase. The pull request now contains 28 commits: > > - Merge branch 'JDK-8295159' of https://github.com/theRealAph/jdk into > JDK-8295159 > - Fix LLVM > - Give x32 bug its own ID. > - cleanup > - Fix conditional compilation > - Remove x32 handling > - Stash x86-32 changes > - MacOS > - AArch64 > - x86-32 changes > - ... and 18 more: https://git.openjdk.org/jdk/compare/cef9fff0...c56adbd9 src/hotspot/os/bsd/os_bsd.cpp line 976: > 974: // same architecture as Hotspot is running on > 975: > 976: void *os::Bsd::dlopen_helper(const char *filename, int mode) { I thought BSD is switching to clang. src/hotspot/os/bsd/os_bsd.cpp line 1001: > 999: static const volatile double thresh > 1000: = jdouble_cast(0x0000000000000003); // 0x0.0000000000003p-1022; > 1001: if (unity + thresh == unity || -unity - thresh == -unity) { Could this expression happen to be precomputed by the compiler at build time? Maybe make the parts volatile? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/10661#discussion_r1355064475 PR Review Comment: https://git.openjdk.org/jdk/pull/10661#discussion_r1355059684
