[Warnings] Silence more warnings (#2699)

* [Warnings] Silence more warnings

Unused variables and missing switch case.

* Move static global var to the host_tensor translation unit

- Remove non-portable 'unused' attribute.

* Fix style

src/ngraph/runtime/cpu/cpu_emitter.cpp

@@ -3556,12 +3556,13 @@ namespace ngraph
                         func_block += "d_" + out_denom + " = 1;\n";
                     }
                     break;
-                }
-                if (func_block.empty())
-                {
+                default:
                     throw ngraph_error(
                         "generate_sigmoid_mul_func input function type not supported");
                 }
+
+                NGRAPH_ASSERT(!func_block.empty()) << "'func_block' must not be empty";
+
                 return func_block;
             }
             template <>

src/ngraph/runtime/host_tensor.cpp

@@ -24,6 +24,8 @@
 using namespace ngraph;
 using namespace std;
 
+static const size_t alignment = 64;
+
 runtime::HostTensor::HostTensor(const ngraph::element::Type& element_type,
                                 const Shape& shape,
                                 void* memory_pointer,
@@ -46,7 +48,7 @@ runtime::HostTensor::HostTensor(const ngraph::element::Type& element_type,
     }
     else if (m_buffer_size > 0)
     {
-        size_t allocation_size = m_buffer_size + runtime::alignment;
+        size_t allocation_size = m_buffer_size + alignment;
         m_allocated_buffer_pool = static_cast<char*>(ngraph_malloc(allocation_size));
         m_aligned_buffer_pool = m_allocated_buffer_pool;
         size_t mod = size_t(m_aligned_buffer_pool) % alignment;

src/ngraph/runtime/host_tensor.hpp

@@ -26,8 +26,6 @@ namespace ngraph
 {
     namespace runtime
     {
-        static size_t alignment = 64;
-
         class HostTensor;
     }
 }

test/partial_shape.cpp

@@ -82,8 +82,7 @@ TEST(partial_shape, dim_conversion_dynamic)
 {
     EXPECT_ANY_THROW({
         size_t s{Dimension::dynamic()};
-
-        s = 0; // Silence compiler warning about unused s
+        (void)s; // Silence compiler warning about unused s
     });
 }