Случайные сбои malloc в stringByReplacingOccurrencesOfString

Question

Я получаю случайные сбои malloc в stringByReplacingOccurrencesOfString. Я заметил, что он падает на более длинные строки, но я не могу найти почему. В чем может быть проблема?

Ошибка:

CashTrader(53448,0xb0103000) malloc: *** error for object 0x5c5eca0: incorrect checksum for freed object - object was probably modified after being freed. 

Входной encryptedparams

raStwjnw9uiOEHzF00UazOUp879zUuLwJ6J300BH2DMH29Pww/4mOR3oHXv4F/CL 

Пример кода:

-(NSURL *)createReqUrl:(NSString *)hostString secure:(BOOL)usessl urlRoot:(NSString*)urlRoot encryptedParam:(NSString *)encryptedparams{ 
    NSString *encryptString; 
    encryptString = nil; 



    encryptString = [encryptedparams stringByReplacingOccurrencesOfString:@"+" withString:@"%%2b"]; 
    encryptString = [encryptString stringByReplacingOccurrencesOfString:@"/" withString:@"%%2f"]; 
    encryptString = [encryptString stringByReplacingOccurrencesOfString:@"=" withString:@"%%3d"]; 
    encryptString = [encryptString stringByReplacingOccurrencesOfString:@"@" withString:@"%%40"]; 

    NSString *answer = [[NSString alloc] initWithString:urlRoot]; 
    answer = [[answer stringByAppendingString:encryptString] stringByReplacingOccurrencesOfString:@"%%" withString:@"%"]; 

    NSString *scheme = nil; 
    if (usessl) 
     scheme = @"https://"; 
    else 
     scheme = @"http://"; 

    return [[NSURL alloc] initWithString:[[scheme stringByAppendingString:hostString] stringByAppendingString:answer]];; 
} 

Answer 1

Я верю ваш encryptString должен быть NSMutableString.