[all-commits] [llvm/llvm-project] 782791: [clang][#52782] Bail on incomplete parameter type ...

[zero9178 via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 782791ee84d29db137f441c1e033582a7a78ad5e
      https://github.com/llvm/llvm-project/commit/782791ee84d29db137f441c1e033582a7a78ad5e
  Author: Markus Böck <markus.boeck02 at gmail.com>
  Date:   2022-01-05 (Wed, 05 Jan 2022)

  Changed paths:
    M clang/lib/AST/Mangle.cpp
    A clang/test/CodeGen/pr52782-stdcall-func-decl.cpp

  Log Message:
  -----------
  [clang][#52782] Bail on incomplete parameter type in stdcall name mangling

stdcall name mangling requires a suffix with the number equal to the sum of the byte count of all parameter types. In the case of a function prototype that has a parameter type of an incomplete type it is impossible to get the size of the type. While such a function is not callable or able to be defined in the TU, it may still be mangled when generating debug info, which would previously lead to a crash.
This patch fixes that by simply bailing out of the loop and using the so far accumulated byte count. This matches GCCs behaviour as well: https://github.com/gcc-mirror/gcc/blob/bc8d6c60137f8bbf173b86ddf31b15d7ba2a33dd/gcc/config/i386/winnt.c#L203

Fixes https://github.com/llvm/llvm-project/issues/52782

Differential Revision: https://reviews.llvm.org/D116020