foo.c: In function 'main':
foo.c:6:5: error: too few arguments to function 'printf'
    6 |     printf();
      |     ^~~~~~
In file included from foo.c:1:
/nix/store/3w4yrspgcx1z9wi18rv0hbap4jjlhx4c-glibc-2.37-8-dev/include/stdio.h:356:12: note: declared here
  356 | extern int printf (const char *__restrict __format, ...);
      |            ^~~~~~
foo.c:5:16: warning: unused variable 'b' [-Wunused-variable]
    5 |         int a, b;
      |                ^
foo.c:5:13: warning: unused variable 'a' [-Wunused-variable]
    5 |         int a, b;
      |             ^

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