foo.c: In function 'main':
foo.c:6:10: error: 't' undeclared (first use in this function)
    6 |  if(b<a) t=b;b=a;a=t;
      |          ^
foo.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
    6 |  if(b<a) t=b;b=a;a=t;
      |  ^~
foo.c:6:14: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
    6 |  if(b<a) t=b;b=a;a=t;
      |              ^
foo.c:7:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
    7 |  if(c<b) t=c;c=b;b=t;
      |  ^~
foo.c:7:14: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
    7 |  if(c<b) t=c;c=b;b=t;
      |              ^

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