小数部位该为0却不是0

pasuka

C1数组没有赋初值，与aa结果不一致又有啥奇怪呢？

-finit-local-zero
-finit-derived
-finit-integer=n
-finit-real=<zero|inf|-inf|nan|snan>
-finit-logical=<true|false>
-finit-character=n
The -finit-local-zero option instructs the compiler to initialize local INTEGER, REAL, and COMPLEX variables to zero, LOGICAL variables to false, and CHARACTER variables to a string of null bytes. Finer-grained initialization options are provided by the -finit-integer=n, -finit-real=<zero|inf|-inf|nan|snan> (which also initializes the real and imaginary parts of local COMPLEX variables), -finit-logical=<true|false>, and -finit-character=n (where n is an ASCII character value) options. Components of derived type variables will be initialized according to these flags only with -finit-derived. These options do not initialize

allocatable arrays
variables that appear in an EQUIVALENCE statement.
(These limitations may be removed in future releases).

Note that the -finit-real=nan option initializes REAL and COMPLEX variables with a quiet NaN. For a signalling NaN use -finit-real=snan; note, however, that compile-time optimizations may convert them into quiet NaN and that trapping needs to be enabled (e.g. via -ffpe-trap).

Finally, note that enabling any of the -finit-* options will silence warnings that would have been emitted by -Wuninitialized for the affected local variables.