diff --git a/fmt/format.cc b/fmt/format.cc
index 4b7c2d24..4c14d0c6 100644
--- a/fmt/format.cc
+++ b/fmt/format.cc
@@ -70,6 +70,11 @@
 # pragma warning(disable: 4996)
 #endif
 
+#ifdef __c2__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunused-function"
+#endif
+
 // Dummy implementations of strerror_r and strerror_s called if corresponding
 // system functions are not available.
 static inline fmt::internal::Null<> strerror_r(int, char *, ...) {
@@ -79,6 +84,10 @@ static inline fmt::internal::Null<> strerror_s(char *, std::size_t, ...) {
   return fmt::internal::Null<>();
 }
 
+#ifdef __c2__
+# pragma clang diagnostic pop
+#endif
+
 namespace fmt {
 
 FMT_FUNC internal::RuntimeError::~RuntimeError() FMT_DTOR_NOEXCEPT {}
@@ -159,6 +168,11 @@ int safe_strerror(
             ERANGE : result;
     }
 
+#ifdef __c2__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+
     // Fallback to strerror if strerror_r and strerror_s are not available.
     int fallback(internal::Null<>) {
       errno = 0;
@@ -166,6 +180,10 @@ int safe_strerror(
       return errno;
     }
 
+#ifdef __c2__
+# pragma clang diagnostic pop
+#endif
+
    public:
     StrError(int err_code, char *&buf, std::size_t buf_size)
       : error_code_(err_code), buffer_(buf), buffer_size_(buf_size) {}
diff --git a/fmt/format.h b/fmt/format.h
index c02a301e..c91bbf60 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -335,7 +335,10 @@ typedef __int64          intmax_t;
 
 namespace fmt {
 namespace internal {
-# pragma intrinsic(_BitScanReverse)
+// avoid Clang with Microsoft CodeGen's -Wunknown-pragmas warning
+# ifndef __clang__
+#  pragma intrinsic(_BitScanReverse)
+# endif
 inline uint32_t clz(uint32_t x) {
   unsigned long r = 0;
   _BitScanReverse(&r, x);
@@ -349,7 +352,8 @@ inline uint32_t clz(uint32_t x) {
 }
 # define FMT_BUILTIN_CLZ(n) fmt::internal::clz(n)
 
-# ifdef _WIN64
+// avoid Clang with Microsoft CodeGen's -Wunknown-pragmas warning
+# if defined(_WIN64) && !defined(__clang__)
 #  pragma intrinsic(_BitScanReverse64)
 # endif