Fixes #153

src/rewriter.fs

@@ -478,7 +478,7 @@ module private RewriterImpl =
     let simplifyStmt = function
         | Block [] as e -> e
         | Block b -> match simplifyBlock b with
-                        | [stmt] -> stmt
+                        | [stmt] as b when hasNoDecl b -> stmt
                         | stmts -> Block stmts
         | Decl (ty, li) -> Decl (rwType ty, declsNotToInline li)
         | ForD ((ty, d), cond, inc, body) -> ForD((rwType ty, declsNotToInline d), cond, inc, squeezeBlockWithComma body)

tests/unit/shadowing.frag

@@ -12,4 +12,51 @@ float g(float f)
 		f+=g;
 	}
 	return f;
+}
+
+int m1()
+{
+	int x = 1;
+	if (rand() >.5)
+	{
+		int x = 2, y = x; // y is initialized to 2
+		return y;
+	}
+}
+
+struct S{ int x; };
+
+S m2()
+{
+	S S = S(0); // 'S' is only visible as a struct and constructor
+	return S; // 'S' is now visible as a variable
+}
+
+void m4(int k)
+{
+	//int k = k + 3; // redeclaration error of the name k
+	{
+		int k = k + 3; // 2nd k is parameter, initializing nested first k
+		int m = k; // use of new k, which is hiding the parameter
+	}
+	return k;
+
+	//int x = x; // Error if x has not been previously defined.
+	// If the previous definition of x was in this
+	// same scope, this causes a redeclaration error.
+}
+
+void m5(float k)
+{
+	float m = 9.;
+	m = 14.;
+	{
+		float k = k + 3.; // 2nd k is parameter, initializing nested first k
+		m = k; // use of new k, which is hiding the parameter
+	}
+	return k + 2. * m;
+}
+void m6()
+{
+	m5(55.);
 }

tests/unit/shadowing.frag.expected

@@ -13,3 +13,28 @@ float g(float f)
   }
   return f;
 }
+int m1()
+{
+  if(rand()>.5)
+    return 2;
+}
+struct S{int x;};
+S m2()
+{
+  return S(0);
+}
+void m4(int k)
+{
+  return k;
+}
+void m5()
+{
+  float m=9.;
+  m=14.;
+  m=58.;
+  return 55.+2.*m;
+}
+void m6()
+{
+  m5();
+}