C++ Convertion Char Int Arm
I Have This Very Simple C++ Code: #Include Int Main() { Std: :Cout Output: -2 Windows 10 X64 Msvc 2017 -> Output: -2 Macos X64 Clang -> Output -2 Ubuntu Armv8...
I have this very simple C++ code :
#include <iostream>
int main() {
std::cout << (int)(char)(int)char(-2);
return 0;
}
I am executing it on different setups :
- Ubuntu 20.04 x64 (g++) -> Output : -2
- Windows 10 x64 MSVC 2017 -> Output : -2
- MacOS x64 Clang -> Output -2
- Ubuntu Armv8 (g++) / EC2 Instance -> Output : 254
I want to obtain -2 all the time, and I don't understand this difference in behavior.
Does anyone have any idea?
3 Answers
A compiler is allowed to choose if char is signed or unsigned. The standard says that they have to pick, but don't mandate which way they choose.
GCC supports -fsigned-char and -funsigned-char to force this behavior.
From the ISO C++ International Standard (Tip of trunk):
§6.8.2 Fundamental Types |
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