From c7d9dfe810d250db7ce58b4f27fe901dd9715901 Mon Sep 17 00:00:00 2001
From: Ed Maste <emaste@FreeBSD.org>
Date: Thu, 7 May 2020 21:18:37 +0000
Subject: [PATCH] Merge commit 21e5e1724b75 from llvm git:

  getMainExecutable: Fix hand-rolled AT_EXECPATH for older FreeBSD

  Once we hit AT_NULL, we need to bail out of the loop; not just the
  enclosing switch.  This fixes basic usage (e.g. `cc --version`) when
  AT_EXECPATH isn't present on older branches (e.g. under
  emu-user-static, at the moment), where we would previously run off
  the end of ::environ.

  Patch By: kevans

  Reviewed By: arichardson

  Differential Revision:  https://reviews.llvm.org/D79239

MFC after:	3 days
---
 contrib/llvm-project/llvm/lib/Support/Unix/Path.inc | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc b/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
index 2a03dc682bce..9b902f15fc09 100644
--- a/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
+++ b/contrib/llvm-project/llvm/lib/Support/Unix/Path.inc
@@ -208,14 +208,9 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
   while (*p++ != 0)
     ;
   // Iterate through auxiliary vectors for AT_EXECPATH.
-  for (;;) {
-    switch (*(uintptr_t *)p++) {
-    case AT_EXECPATH:
+  for (; *(uintptr_t *)p != AT_NULL; p++) {
+    if (*(uintptr_t *)p++ == AT_EXECPATH)
       return *p;
-    case AT_NULL:
-      break;
-    }
-    p++;
   }
 #endif
   // Fall back to argv[0] if auxiliary vectors are not available.