fix some oss-fuzz (#1218)

* fix oss-fuzz 18138.

* fix oss-fuzz 20079.

* fix oss-fuzz 20209.

* fix oss-fuzz 20210.

* fix oss-fuzz 20262.

* rollback.

* rollback.

* fix oss-fuzz 20079.

* fix oss-fuzz 20179.

* fix oss-fuzz 20195.

* fix oss-fuzz 20206.

* fix oss-fuzz 20207.

* fix oss-fuzz 20265.

* fix oss-fuzz 20285.

* fix oss-fuzz 20868.

* fix oss-fuzz 20908.

* fix oss-fuzz 20909.

* fix oss-fuzz 20914.

* fix oss-fuzz 20922.

* fix oss-fuzz 20928.

* remove warnigs.

qemu/fpu/softfloat.c

@@ -2974,7 +2974,7 @@ int32 float64_to_int32_round_to_zero( float64 a STATUS_PARAM )
     savedASig = aSig;
     aSig >>= shiftCount;
     z = (int32_t)aSig;
-    if ( aSign ) z = - z;
+    if ( aSign && (z != 0x80000000)) z = - z;
     if ( ( z < 0 ) ^ aSign ) {
  invalid:
         float_raise( float_flag_invalid STATUS_VAR);