Fix compiler warning

david-rowley · david-rowley · commit fe4f36bcde18 · 2020-09-15T15:07:57.000+12:00
Introduced in 0aa8f76. MSVC warned about performing 32-bit bit shifting when it appeared like we might like a 64-bit result. We did, but it just so happened that none of the calls to this function could have caused the 32-bit shift to overflow. Here we just cast the constant to int64 to make the compiler happy. Discussion: https://postgr.es/m/CAApHDvofA_vsrpC13mq_hZyuye5B-ssKEaer04OouXYCO5-uXQ@mail.gmail.com
diff --git a/src/backend/utils/adt/dbsize.c b/src/backend/utils/adt/dbsize.c
@@ -627,7 +627,7 @@ numeric_shift_right(Numeric n, unsigned count)
 	Datum		divisor_numeric;
 	Datum		result;
 
-	divisor_numeric = NumericGetDatum(int64_to_numeric(1 << count));
+	divisor_numeric = NumericGetDatum(int64_to_numeric(((int64) 1) << count));
 	result = DirectFunctionCall2(numeric_div_trunc, d, divisor_numeric);
 	return DatumGetNumeric(result);
 }

Original file line number	Diff line number	Diff line change
`@@ -627,7 +627,7 @@ numeric_shift_right(Numeric n, unsigned count)`
`627`	`627`	`Datum divisor_numeric;`
`628`	`628`	`Datum result;`
`629`	`629`
`630`		`- divisor_numeric = NumericGetDatum(int64_to_numeric(1 << count));`
	`630`	`+ divisor_numeric = NumericGetDatum(int64_to_numeric(((int64) 1) << count));`
`631`	`631`	`result = DirectFunctionCall2(numeric_div_trunc, d, divisor_numeric);`
`632`	`632`	`return DatumGetNumeric(result);`
`633`	`633`	`}`