Adding option -fno-inline-asm to disallow inline asm

Summary:
This patch add a new option to dis-allow all inline asm.
Any GCC style inline asm will be reported as an error.

Reviewers: rnk, echristo

Reviewed By: rnk, echristo

Subscribers: bob.wilson, rnk, echristo, rsmith, cfe-commits

Differential Revision: http://reviews.llvm.org/D6870

llvm-svn: 226340
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index d625c0e..db43fde 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -4320,6 +4320,11 @@
                    false))
     CmdArgs.push_back("-fasm-blocks");
 
+  // -fgnu-inline-asm is default.
+  if (!Args.hasFlag(options::OPT_fgnu_inline_asm,
+                    options::OPT_fno_gnu_inline_asm, true))
+    CmdArgs.push_back("-fno-gnu-inline-asm");
+
   // Enable vectorization per default according to the optimization level
   // selected. For optimization levels that want vectorization we use the alias
   // option to simplify the hasFlag logic.