diff --git a/libcpuid/CMakeLists.txt b/libcpuid/CMakeLists.txt
index 67efebe..1a10ccc 100644
--- a/libcpuid/CMakeLists.txt
+++ b/libcpuid/CMakeLists.txt
@@ -20,6 +20,12 @@ if("${MSVC_CXX_ARCHITECTURE_ID}" MATCHES "x64")
   list(APPEND cpuid_sources masm-x64.asm)
 endif()
 
+option(SUPPORT_DEPRECATED "Build support of deprecated attributes" ON)
+if(NOT SUPPORT_DEPRECATED)
+  message(AUTHOR_WARNING "Deprecated attributes will not be available, the library will be not backward compatible")
+  add_compile_definitions(LIBCPUID_DISABLE_DEPRECATED)
+endif(NOT SUPPORT_DEPRECATED)
+
 add_library(cpuid ${cpuid_sources})
 set_property(TARGET cpuid PROPERTY WINDOWS_EXPORT_ALL_SYMBOLS ON)
 target_include_directories(cpuid SYSTEM PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>)
diff --git a/libcpuid/cpuid_main.c b/libcpuid/cpuid_main.c
index 0b47460d..09d1618 100644
--- a/libcpuid/cpuid_main.c
+++ b/libcpuid/cpuid_main.c
@@ -80,8 +80,8 @@ static void cpu_id_t_constructor(struct cpu_id_t* id)
 	id->feature_level = FEATURE_LEVEL_UNKNOWN;
 	id->vendor = VENDOR_UNKNOWN;
 	id->l1_data_cache = id->l1_instruction_cache = id->l2_cache = id->l3_cache = id->l4_cache = -1;
-	id->l1_assoc = id->l1_data_assoc = id->l1_instruction_assoc = id->l2_assoc = id->l3_assoc = id->l4_assoc = -1;
-	id->l1_cacheline = id->l1_data_cacheline = id->l1_instruction_cacheline = id->l2_cacheline = id->l3_cacheline = id->l4_cacheline = -1;
+	id->l1_data_assoc = id->l1_instruction_assoc = id->l2_assoc = id->l3_assoc = id->l4_assoc = -1;
+	id->l1_data_cacheline = id->l1_instruction_cacheline = id->l2_cacheline = id->l3_cacheline = id->l4_cacheline = -1;
 	id->l1_data_instances = id->l1_instruction_instances = id->l2_instances = id->l3_instances = id->l4_instances = -1;
 	id->x86.sse_size = -1;
 	init_affinity_mask(&id->affinity_mask);
@@ -1376,8 +1376,11 @@ int cpu_ident_internal(struct cpu_raw_data_t* raw, struct cpu_id_t* data, struct
 			r = cpuid_identify_arm(raw, data);
 			break;
 		default:
-			return cpuid_set_error(ERR_CPU_UNKN);
+			r = ERR_CPU_UNKN;
+			break;
 	}
+
+#ifndef LIBCPUID_DISABLE_DEPRECATED
 	/* Backward compatibility */
 	/* - Deprecated since v0.5.0 */
 	data->l1_assoc     = data->l1_data_assoc;
@@ -1390,6 +1393,7 @@ int cpu_ident_internal(struct cpu_raw_data_t* raw, struct cpu_id_t* data, struct
 	data->ext_model  = data->x86.ext_model;
 	data->sse_size   = data->x86.sse_size;
 	data->sgx        = data->x86.sgx;
+#endif /* LIBCPUID_DISABLE_DEPRECATED */
 
 	return cpuid_set_error(r);
 }
diff --git a/libcpuid/libcpuid.h b/libcpuid/libcpuid.h
index 5231624..816f5b1 100644
--- a/libcpuid/libcpuid.h
+++ b/libcpuid/libcpuid.h
@@ -523,6 +523,7 @@ struct cpu_id_t {
 	 */
 	uint8_t flags[CPU_FLAGS_MAX];
 
+#ifndef LIBCPUID_DISABLE_DEPRECATED
 	/**
 	 * CPU family (BaseFamily[3:0])
 	 * @deprecated replaced by \ref x86_id_t::family (prefix member with `x86.`, e.g. `id.x86.family`)
@@ -558,6 +559,7 @@ struct cpu_id_t {
 	 */
 	LIBCPUID_DEPRECATED("replace with '.x86.ext_model' in your code to fix the warning")
 	int32_t ext_model;
+#endif /* LIBCPUID_DISABLE_DEPRECATED */
 
 	/**
 	 * contains architecture specific info.
@@ -620,11 +622,13 @@ struct cpu_id_t {
 	/** L4 cache size in KB. Zero on most systems */
 	int32_t l4_cache;
 
+#ifndef LIBCPUID_DISABLE_DEPRECATED
 	/** Cache associativity for the L1 data cache. -1 if undetermined
 	 * @deprecated replaced by \ref cpu_id_t::l1_data_assoc
 	 */
 	LIBCPUID_DEPRECATED("replace with 'l1_data_assoc' in your code to fix the warning")
 	int32_t l1_assoc;
+#endif /* LIBCPUID_DISABLE_DEPRECATED */
 
 	/** Cache associativity for the L1 data cache. -1 if undetermined */
 	int32_t l1_data_assoc;
@@ -641,11 +645,13 @@ struct cpu_id_t {
 	/** Cache associativity for the L4 cache. -1 if undetermined */
 	int32_t l4_assoc;
 
+#ifndef LIBCPUID_DISABLE_DEPRECATED
 	/** Cache-line size for L1 data cache. -1 if undetermined
 	 * @deprecated replaced by \ref cpu_id_t::l1_data_cacheline
 	 */
 	LIBCPUID_DEPRECATED("replace with 'l1_data_cacheline' in your code to fix the warning")
 	int32_t l1_cacheline;
+#endif /* LIBCPUID_DISABLE_DEPRECATED */
 
 	/** Cache-line size for L1 data cache. -1 if undetermined */
 	int32_t l1_data_cacheline;
diff --git a/libcpuid/rdmsr.c b/libcpuid/rdmsr.c
index 125a791..67d030d 100644
--- a/libcpuid/rdmsr.c
+++ b/libcpuid/rdmsr.c
@@ -734,13 +734,13 @@ static int msr_platform_info_supported(struct msr_info_t *info)
 
 	if(info->id->vendor == VENDOR_INTEL) {
 		for(i = 0; i < COUNT_OF(msr_platform_info); i++) {
-			if((info->id->ext_family == msr_platform_info[i].ext_family) && (info->id->ext_model == msr_platform_info[i].ext_model)) {
-				debugf(2, "Intel CPU with CPUID signature %02X_%02XH supports MSR_PLATFORM_INFO.\n", info->id->ext_family, info->id->ext_model);
+			if((info->id->x86.ext_family == msr_platform_info[i].ext_family) && (info->id->x86.ext_model == msr_platform_info[i].ext_model)) {
+				debugf(2, "Intel CPU with CPUID signature %02X_%02XH supports MSR_PLATFORM_INFO.\n", info->id->x86.ext_family, info->id->x86.ext_model);
 				supported = 1;
 				return supported;
 			}
 		}
-		debugf(2, "Intel CPU with CPUID signature %02X_%02XH does not support MSR_PLATFORM_INFO.\n", info->id->ext_family, info->id->ext_model);
+		debugf(2, "Intel CPU with CPUID signature %02X_%02XH does not support MSR_PLATFORM_INFO.\n", info->id->x86.ext_family, info->id->x86.ext_model);
 	}
 
 	supported = 0;
@@ -830,13 +830,13 @@ static int msr_perf_status_supported(struct msr_info_t *info)
 
 	if(info->id->vendor == VENDOR_INTEL) {
 		for(i = 0; i < COUNT_OF(msr_perf_status); i++) {
-			if((info->id->ext_family == msr_perf_status[i].ext_family) && (info->id->ext_model == msr_perf_status[i].ext_model)) {
-				debugf(2, "Intel CPU with CPUID signature %02X_%02XH supports MSR_PERF_STATUS.\n", info->id->ext_family, info->id->ext_model);
+			if((info->id->x86.ext_family == msr_perf_status[i].ext_family) && (info->id->x86.ext_model == msr_perf_status[i].ext_model)) {
+				debugf(2, "Intel CPU with CPUID signature %02X_%02XH supports MSR_PERF_STATUS.\n", info->id->x86.ext_family, info->id->x86.ext_model);
 				supported = 1;
 				return supported;
 			}
 		}
-		debugf(2, "Intel CPU with CPUID signature %02X_%02XH does not support MSR_PERF_STATUS.\n", info->id->ext_family, info->id->ext_model);
+		debugf(2, "Intel CPU with CPUID signature %02X_%02XH does not support MSR_PERF_STATUS.\n", info->id->x86.ext_family, info->id->x86.ext_model);
 	}
 
 	supported = 0;