Fix a crash on function-static variables with initializers (#703)

This code path hadn't been used, and it had a crash due to not inserting the basic blocks it created (for initializing the variable) into the parent function. The fix adds a bit more smarts to the `IRBuilder` to help with inserting basic blocks into the flow of a function.

The actual user issue was around `static const` declarations, and it is clear that the code is incorrectly treating a function local `static const` as if it were just `static`. That will need to be fixed in another change.

1 files changed, 3 insertions, 2 deletions

diff --git a/source/slang/lower-to-ir.cpp b/source/slang/lower-to-ir.cpp
index 6cce469ea..806654ccb 100644
--- a/source/slang/lower-to-ir.cpp
+++ b/source/slang/lower-to-ir.cpp
@@ -4012,18 +4012,19 @@ struct DeclLoweringVisitor : DeclVisitor<DeclLoweringVisitor, LoweredValInfo>
             // generating the code we actually care about, back in the original function.
 
             auto builder = getBuilder();
+
             auto initBlock = builder->createBlock();
             auto afterBlock = builder->createBlock();
 
             builder->emitIfElse(getSimpleVal(context, boolVal), afterBlock, initBlock, afterBlock);
 
-            builder->setInsertInto(initBlock);
+            builder->insertBlock(initBlock);
             LoweredValInfo initVal = lowerLValueExpr(context, initExpr);
             assign(context, globalVal, initVal);
             assign(context, boolVal, LoweredValInfo::simple(builder->getBoolValue(true)));
             builder->emitBranch(afterBlock);
 
-            builder->setInsertInto(afterBlock);
+            builder->insertBlock(afterBlock);
         }
 
         irGlobal->moveToEnd();