View difference between Paste ID: nLzRGHr0 and c0mTmL2K

 // Compile on a recent version of clang and run it:
 // clang++ -std=c++11 -O3 -Wall -fsanitize=undefined stdint16.cpp -o stdint16
 //
 // You'll get a nice error:
-// main.cpp:20:55: runtime error: signed integer overflow: 65535 * 65535 cannot be represented in type 'int'
+// main.cpp:21:37: runtime error: signed integer overflow: 65535 * 65535
 //     cannot be represented in type 'int'
 //
 // What's just awesome about this is that avoiding this problem portably (i.e.
 // without depending upon a particular size of "int") requires a maze of "if"
 // or "#if" statements or doing your multiplications using uintmax_t.  Great
 // solution, huh? >.<
 //
 
 #include <cinttypes>
 #include <cstdint>
 #include <cstdio>
 
 int main()
-     std::uint8_t a =  UINT8_C(              0xFF); a *= a; // OK
+
-    std::uint16_t b = UINT16_C(            0xFFFF); b *= b; // undefined!
+     std::uint8_t a =  UINT8_MAX; a *= a; // OK
-    std::uint32_t c = UINT32_C(        0xFFFFFFFF); c *= c; // OK
+    std::uint16_t b = UINT16_MAX; b *= b; // undefined!
-    std::uint64_t d = UINT64_C(0xFFFFFFFFFFFFFFFF); d *= d; // OK
+    std::uint32_t c = UINT32_MAX; c *= c; // OK
     std::uint64_t d = UINT64_MAX; d *= d; // OK
-    std::printf("%02" PRIX8 " %04" PRIX16 " %08" PRIX32 " %016" PRIX64 "\n", a, b, c, d);
+
     std::printf("%02" PRIX8 " %04" PRIX16 " %08" PRIX32 " %016" PRIX64 "\n",
         a, b, c, d);
 
     return 0;
 }