Really fix FreeBSD, which apparently doesn't tolerate the extern.
Thanks to Jeff Cohen for pointing out my goof.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16762 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CBackend/Writer.cpp b/lib/Target/CBackend/Writer.cpp
index 85229ad..bdc8b8d 100644
--- a/lib/Target/CBackend/Writer.cpp
+++ b/lib/Target/CBackend/Writer.cpp
@@ -702,10 +702,11 @@
 static void generateCompilerSpecificCode(std::ostream& Out) {
   // Alloca is hard to get, and we don't want to include stdlib.h here...
   Out << "/* get a declaration for alloca */\n"
-      << "#if defined(sun) || defined(__CYGWIN__) || defined(__APPLE__) || "
-      << "defined(__FreeBSD__)\n"
+      << "#if defined(sun) || defined(__CYGWIN__) || defined(__APPLE__)\n"
       << "extern void *__builtin_alloca(unsigned long);\n"
       << "#define alloca(x) __builtin_alloca(x)\n"
+      << "#elif defined(__FreeBSD__)\n"
+      << "#define alloca(x) __builtin_alloca(x)\n"
       << "#else\n"
       << "#include <alloca.h>\n"
       << "#endif\n\n";