CODEWITHSUNDEEP
c
Lex Alex
Lex Alex

Reputation: 29

this decimal constant is unsigned only in ISO C90

stackoverflowers :> (Can i say that? :| ) OK... this time i want to know if this warning should be solved, or should be ignored. It represent the number of experience needed for advancing at next level. (for a game) This is the error: warning: this decimal constant is unsigned only in ISO C90 And this is the file: ( I will show just a part of the code, it is pretty much long :D.)

const DWORD exp_table_common[PLAYER_EXP_TABLE_MAX + 1] =
{

2150000000, //  100
2210000000,     
2250000000,     
2280000000,     
2310000000,     
2330000000, //  105
2350000000,     
2370000000,     
2390000000,     
2400000000,     
2410000000, //  110
2420000000,     
2430000000,     
2440000000,     
2450000000,     
2460000000, //  115
2470000000,     
2480000000,     
2490000000,     
2490000000,     
2500000000, //  120
};

This are just the warned rows.

Upvotes: 0

Views: 3253

Answers (1)

chux
chux

Reputation: 153547

In C90, a decimal constant gets the type it first fits into

int, long, unsigned long

In C99 onward, a decimal constant gets the type it first fits into

int, long, long long

In your system, 2150000000 is bigger than LONG_MAX (certainly 2147483647). So with a C90 compiler, it is unsigned long. With current compilers, it is long long.

Should you ignore? It depends on subsequent code. Recommended to not ignore and explicitly declaring the decimal constant as an unsigned one by appending the u suffix like 2500000000u.

Upvotes: 3

Related Questions