diff --git a/src/ciphers/aes/aes_desc.c b/src/ciphers/aes/aes_desc.c
index b9d1d5089..1c08c713a 100644
--- a/src/ciphers/aes/aes_desc.c
+++ b/src/ciphers/aes/aes_desc.c
@@ -15,14 +15,14 @@
 #define LTC_S_X86_CPUID
 static LTC_INLINE void s_x86_cpuid(int* regs, int leaf)
 {
-#if defined _MSC_VER
+#if defined(_MSC_VER) && !defined(__clang__) // MSVC but not ClangCL
    __cpuid(regs, leaf);
 #else
    int a, b, c, d;
 
    a = leaf;
    b = c = d = 0;
-   asm volatile ("cpuid"
+   __asm__ volatile ("cpuid"
        :"=a"(a), "=b"(b), "=c"(c), "=d"(d)
        :"a"(a), "c"(c)
    );
diff --git a/src/encauth/gcm/gcm_gf_mult.c b/src/encauth/gcm/gcm_gf_mult.c
index 637438a03..1053071b2 100644
--- a/src/encauth/gcm/gcm_gf_mult.c
+++ b/src/encauth/gcm/gcm_gf_mult.c
@@ -33,14 +33,14 @@
 #define LTC_S_X86_CPUID
 static LTC_INLINE void s_x86_cpuid(int* regs, int leaf)
 {
-#if defined _MSC_VER
+#if defined(_MSC_VER) && !defined(__clang__) // MSVC but not ClangCL
    __cpuid(regs, leaf);
 #else
    int a, b, c, d;
 
    a = leaf;
    b = c = d = 0;
-   asm volatile ("cpuid"
+   __asm__ volatile ("cpuid"
        :"=a"(a), "=b"(b), "=c"(c), "=d"(d)
        :"a"(a), "c"(c)
    );
diff --git a/src/hashes/sha1_desc.c b/src/hashes/sha1_desc.c
index 8b83687ea..9eaad2626 100644
--- a/src/hashes/sha1_desc.c
+++ b/src/hashes/sha1_desc.c
@@ -28,14 +28,14 @@ const struct ltc_hash_descriptor sha1_desc =
 #define LTC_S_X86_CPUID
 static LTC_INLINE void s_x86_cpuid(int* regs, int leaf)
 {
-#if defined _MSC_VER
+#if defined(_MSC_VER) && !defined(__clang__) // MSVC but not ClangCL
    __cpuid(regs, leaf);
 #else
     int a, b, c, d;
 
     a = leaf;
     b = c = d = 0;
-    asm volatile ("cpuid"
+    __asm__ volatile ("cpuid"
         :"=a"(a), "=b"(b), "=c"(c), "=d"(d)
         :"a"(a), "c"(c)
     );
diff --git a/src/hashes/sha2/sha224_desc.c b/src/hashes/sha2/sha224_desc.c
index 6aa9dfd20..3269ff987 100644
--- a/src/hashes/sha2/sha224_desc.c
+++ b/src/hashes/sha2/sha224_desc.c
@@ -33,14 +33,14 @@ const struct ltc_hash_descriptor sha224_desc =
 #define LTC_S_X86_CPUID
 static LTC_INLINE void s_x86_cpuid(int* regs, int leaf)
 {
-#if defined _MSC_VER
+#if defined(_MSC_VER) && !defined(__clang__) // MSVC but not ClangCL
    __cpuid(regs, leaf);
 #else
     int a, b, c, d;
 
     a = leaf;
     b = c = d = 0;
-    asm volatile ("cpuid"
+    __asm__ volatile ("cpuid"
         :"=a"(a), "=b"(b), "=c"(c), "=d"(d)
         :"a"(a), "c"(c)
     );
diff --git a/src/hashes/sha2/sha256_desc.c b/src/hashes/sha2/sha256_desc.c
index 1bf0c1f7a..02b9b0aa7 100644
--- a/src/hashes/sha2/sha256_desc.c
+++ b/src/hashes/sha2/sha256_desc.c
@@ -8,14 +8,14 @@
 #define LTC_S_X86_CPUID
 static LTC_INLINE void s_x86_cpuid(int* regs, int leaf)
 {
-#if defined _MSC_VER
+#if defined(_MSC_VER) && !defined(__clang__) // MSVC but not ClangCL
    __cpuid(regs, leaf);
 #else
     int a, b, c, d;
 
     a = leaf;
     b = c = d = 0;
-    asm volatile ("cpuid"
+    __asm__ volatile ("cpuid"
         :"=a"(a), "=b"(b), "=c"(c), "=d"(d)
         :"a"(a), "c"(c)
     );