[PATCH] D35438: CodeGen: Ensure there is basic block when performing address space cast

[John McCall via Phabricator via cfe-commits]

rjmccall added a comment.

Oh, of course.  Sadly, in C/C++ the declaration point of a variable does not necessarily dominate all uses of the variable, so you need to emit the cast immediately after the alloca.  Just temporarily move CGF.Builder to that point; hopefully we can assume that this function will never try to add control flow.

Test case:

  extern void use(int*);
  void foo() {
    goto later;
    int x;
    later:
    use(&x);
  }


https://reviews.llvm.org/D35438