Revert "[ScopDectect] Allow memory accesses with different element types by default"

This reverts commit https://llvm.org/svn/llvm-project/polly/trunk@260853

We unfortunately still have two bugs left which show only up with
-polly-process-unprofitable and which I forgot to test before committing.

llvm-svn: 260854
diff --git a/polly/lib/Analysis/ScopDetection.cpp b/polly/lib/Analysis/ScopDetection.cpp
index 0e10fc1..3d24596 100644
--- a/polly/lib/Analysis/ScopDetection.cpp
+++ b/polly/lib/Analysis/ScopDetection.cpp
@@ -124,7 +124,7 @@
 static cl::opt<bool> AllowDifferentTypes(
     "polly-allow-differing-element-types",
     cl::desc("Allow different element types for array accesses"), cl::Hidden,
-    cl::init(true), cl::ZeroOrMore, cl::cat(PollyCategory));
+    cl::init(false), cl::ZeroOrMore, cl::cat(PollyCategory));
 
 static cl::opt<bool>
     AllowNonAffine("polly-allow-nonaffine",