[llvm-bugs] [Bug 42680] New: WebAssembly: libc++abi and clang disagree and width of guard variables in __cxa_guard_acquire/release

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=42680

            Bug ID: 42680
           Summary: WebAssembly: libc++abi and clang disagree and width of
                    guard variables in __cxa_guard_acquire/release
           Product: libc++abi
           Version: unspecified
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: All Bugs
          Assignee: unassignedbugs at nondot.org
          Reporter: sbc at chromium.org
                CC: llvm-bugs at lists.llvm.org, mclow.lists at gmail.com

In ItaniumCXXABI.cpp we set UseARMGuardVarABI=true for WebAssembly, but in
cxxabi.h we only set the guard type to 32-bit on arm.

This means that clang allocates 4 butes for the guard but libc++abi will assume
it 8 bytes and clobber memory on __cxa_guard_acquire/__cxa_guard_release.

I suggest we simply stop setting UseARMGuardVarABI unless there was a good
reason for doing this?

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20190718/7dacccff/attachment.html>