foo.c: In function 'main':
foo.c:13:33: warning: implicit declaration of function 'sqrt' [-Wimplicit-function-declaration]
13 | int n = sqrt(xxx);
| ^~~~
foo.c:2:1: note: include '<math.h>' or provide a declaration of 'sqrt'
1 | #include <stdio.h>
+++ |+#include <math.h>
2 |
foo.c:13:33: warning: incompatible implicit declaration of built-in function 'sqrt' [-Wbuiltin-declaration-mismatch]
13 | int n = sqrt(xxx);
| ^~~~
foo.c:13:33: note: include '<math.h>' or provide a declaration of 'sqrt'
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