V541. It is dangerous to print a string into itself.
The analyzer detected a potential error: a string gets printed inside itself. This may lead to unexpected results.
Look at this sample:
char s = "test"; sprintf(s, "N = %d, S = %s", 123, s);
In this code, the 's' buffer is used simultaneously as a buffer for a new string and as one of the elements making up the text. The programmer intends to get this string:
N = 123, S = test
But actually this code will cause creating the following string:
N = 123, S = N = 123, S =
In other cases, such code can lead not only to the output of incorrect text, but also to the buffer overflow or a program crash. To fix the code, we should use a new buffer to save the result. This is the correct code:
char s1 = "test"; char s2; sprintf(s2, "N = %d, S = %s", 123, s1);
This diagnostic is classified as:
You can look at examples of errors detected by the V541 diagnostic.