decimal digit terminates octal escape sequence
An octal escape sequence in a character or string constant was terminated by a decimal digit.
The compiler evaluated the octal number without the decimal digit and assumed the decimal digit was a character.
The following example generates this warning:
char array1[] = "\\709";
If the digit 9 was intended as a character and was not a typing error, correct the example as follows:
char array[] = "\\0709"; /* String containing "89" */