PR20844: If we fail to list-initialize a reference, map to the referenced type
before retrying the initialization to produce diagnostics. Otherwise, we may
fail to produce any diagnostics, and silently produce invalid AST in a -Asserts
build. Also add a note to this codepath to make it more clear why we were
trying to create a temporary.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@217197 91177308-0d34-0410-b5e6-96231b3b80d8
Don't emit prologues or epilogues for naked functions (PR18791, PR20028)

For naked functions with parameters, Clang would still emit stores in the prologue
that would clobber the stack, because LLVM doesn't set up a stack frame. (This
shows up in -O0 compiles, because the stores are optimized away otherwise.)

For example:

  __attribute__((naked)) int f(int x) {
    asm("movl $42, %eax");
    asm("retl");
  }

Would result in:

  _Z1fi:
  movl    12(%esp), %eax
  movl    %eax, (%esp)    <--- Oops.
  movl    $42, %eax
  retl

Differential Revision: http://reviews.llvm.org/D5183

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@217198 91177308-0d34-0410-b5e6-96231b3b80d8
Don't allow non-ASM statements in naked functions

Naked functions don't have prologues or epilogues, so doing
codegen for anything other than inline assembly would be completely
hit or miss.

Differential Revision: http://reviews.llvm.org/D5183

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@217199 91177308-0d34-0410-b5e6-96231b3b80d8
Don't allow inline asm statements to reference parameters in naked functions

Differential Revision: http://reviews.llvm.org/D5183

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@217200 91177308-0d34-0410-b5e6-96231b3b80d8