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No exception raised for Out Of Range input of numbers #647
Description
Hello,
if one has values that are beyond the range of the target type no exception is raised.
e.g. this code with a value of UINT64_MAX+1 and 10000 for the target of a signed char outputs 0 and 16 respectively.
json jtest = json::parse("{\"value\" : 18446744073709551617}");
std::cout << std::to_string(jtest["value"].get<unsigned long long int>()) << "\n";
jtest = json::parse("{\"value\" : 10000}");
std::cout << std::to_string(jtest["value"].get<signed char>()) << "\n";Both cases should throw an exception.
Best regards.
Activity
nlohmann commentedon Jul 5, 2017
The first number is parsed as double and the second as uint64_t. Calling get does not check for overflows - it is just like writing
int i = 12345678901235.1235567.nlohmann commentedon Jul 5, 2017
Remark: an exception is thrown by the parser if the given number does not fit neither the integer types nor the floating-point type.
nlohmann commentedon Jul 6, 2017
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nlohmann commentedon Jul 8, 2017
In fact, Xcode's undefined behavior sanitizer detects the first issue:
However, this is not inside the library, but in the requested conversion from
doubletounsigned long long. I'm not sure whether adding runtime checks to the library would be helpful here.