Fix some assorted compiler warnings on Windows.

Don't overflow the result type of constant expressions.  Don't negate
unsigned types.  Define HAVE_STDBOOL_H for Visual C++ 2013 and later.

Thomas Munro
Reviewed-By: Michael Paquier and Tom Lane

Discussion: https://postgr.es/m/CAEepm%3D3%3DTDYEXUEcHpEx%2BTwc31wo7PA0oBAiNt6sWmq93MW02A%40mail.gmail.com

src/backend/replication/basebackup.c

@@ -1361,7 +1361,7 @@ sendFile(const char *readfilename, const char *tarfilename, struct stat *statbuf
 	char		buf[TAR_SEND_SIZE];
 	uint16		checksum;
 	int			checksum_failures = 0;
-	size_t		cnt;
+	off_t		cnt;
 	int			i;
 	pgoff_t		len = 0;
 	char	   *page;

src/bin/pgbench/pgbench.c

@@ -67,6 +67,7 @@
 #define FNV_PRIME			UINT64CONST(0x100000001b3)
 #define FNV_OFFSET_BASIS	UINT64CONST(0xcbf29ce484222325)
 #define MM2_MUL				UINT64CONST(0xc6a4a7935bd1e995)
+#define MM2_MUL_TIMES_8		UINT64CONST(0x35253c9ade8f4ca8)
 #define MM2_ROT				47
 
 /*
@@ -968,7 +969,7 @@ getHashFnv1a(int64 val, uint64 seed)
 static int64
 getHashMurmur2(int64 val, uint64 seed)
 {
-	uint64		result = seed ^ (sizeof(int64) * MM2_MUL);
+	uint64		result = seed ^ MM2_MUL_TIMES_8;	/* sizeof(int64) */
 	uint64		k = (uint64) val;
 
 	k *= MM2_MUL;

src/include/pg_config.h.win32

@@ -357,7 +357,9 @@
 #define HAVE_SSL_GET_CURRENT_COMPRESSION 1
 
 /* Define to 1 if stdbool.h conforms to C99. */
-/* #undef HAVE_STDBOOL_H */
+#if (_MSC_VER >= 1800)
+#define HAVE_STDBOOL_H 1
+#endif
 
 /* Define to 1 if you have the <stdint.h> header file. */
 /* #undef HAVE_STDINT_H */