Build: Remove causes of pedantic warnings. Addresses issue #352 and PR #242.

SPIRV/SpvBuilder.cpp

@@ -2045,8 +2045,15 @@ Block& Builder::makeNewBlock()
 
 Builder::LoopBlocks& Builder::makeNewLoop()
 {
-    // Older MSVC versions don't allow inlining of blocks below.
-    LoopBlocks blocks = {makeNewBlock(), makeNewBlock(), makeNewBlock(), makeNewBlock()};
+    // This verbosity is needed to simultaneously get the same behavior
+    // everywhere (id's in the same order), have a syntax that works
+    // across lots of versions of C++, have no warnings from pedantic
+    // compilation modes, and leave the rest of the code alone.
+    Block& head            = makeNewBlock();
+    Block& body            = makeNewBlock();
+    Block& merge           = makeNewBlock();
+    Block& continue_target = makeNewBlock();
+    LoopBlocks blocks(head, body, merge, continue_target);
     loops.push(blocks);
     return loops.top();
 }

SPIRV/SpvBuilder.h

@@ -397,7 +397,12 @@ public:
     void endSwitch(std::vector<Block*>& segmentBB);
 
     struct LoopBlocks {
+        LoopBlocks(Block& head, Block& body, Block& merge, Block& continue_target) :
+            head(head), body(body), merge(merge), continue_target(continue_target) { }
         Block &head, &body, &merge, &continue_target;
+    private:
+        LoopBlocks();
+        LoopBlocks& operator=(const LoopBlocks&);
     };
 
     // Start a new loop and prepare the builder to generate code for it.  Until