foo.c: In function 'Mul':
foo.c:23:5: warning: 'xStr' is used uninitialized [-Wuninitialized]
   23 |     printf(xStr, "%d", x);
      |     ^~~~~~~~~~~~~~~~~~~~~
In file included from foo.c:1:
/nix/store/y8wfrgk7br5rfz4221lfb9v8w3n0cnyd-glibc-2.37-8-dev/include/stdio.h:356:12: note: by argument 1 of type 'const char * restrict' to 'printf' declared here
  356 | extern int printf (const char *__restrict __format, ...);
      |            ^~~~~~
foo.c:22:10: note: 'xStr' declared here
   22 |     char xStr[10];
      |          ^~~~

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