foo.c: In function 'main':
foo.c:6:16: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    6 |         for(i=1,i<=4,i++)
      |                ^
foo.c:6:25: error: expected ';' before ')' token
    6 |         for(i=1,i<=4,i++)
      |                         ^
      |                         ;
foo.c:6:25: error: expected expression before ')' token
foo.c:7:24: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    7 |                 for(j=1,j<=i,j++)
      |                        ^
foo.c:7:33: error: expected ';' before ')' token
    7 |                 for(j=1,j<=i,j++)
      |                                 ^
      |                                 ;
foo.c:7:33: error: expected expression before ')' token
foo.c:6:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
    6 |         for(i=1,i<=4,i++)
      |         ^~~
foo.c:9:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
    9 |                 printf("\n");
      |                 ^~~~~~

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