Improve -Wunreachable-code to provide a means to indicate code is intentionally marked dead via if((0)).

Taking a hint from -Wparentheses, use an extra '()' as a sigil that
a dead condition is intentionally dead.  For example:

  if ((0)) { dead }

When this sigil is found, do not emit a dead code warning.  When the
analysis sees:

  if (0)

it suggests inserting '()' as a Fix-It.

llvm-svn: 205069

1 files changed, 4 insertions, 1 deletions

diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp
index ad5cf69cd70..13ac92e86f2 100644
--- a/clang/lib/Analysis/CFG.cpp
+++ b/clang/lib/Analysis/CFG.cpp
@@ -4112,7 +4112,7 @@ void CFGBlock::printTerminator(raw_ostream &OS,
   TPrinter.print(getTerminator());
 }
 
-Stmt *CFGBlock::getTerminatorCondition() {
+Stmt *CFGBlock::getTerminatorCondition(bool StripParens) {
   Stmt *Terminator = this->Terminator;
   if (!Terminator)
     return NULL;
@@ -4171,6 +4171,9 @@ Stmt *CFGBlock::getTerminatorCondition() {
       return Terminator;
   }
 
+  if (!StripParens)
+    return E;
+
   return E ? E->IgnoreParens() : NULL;
 }