Ensure that the argument of shmdt(2) is declared "void *".

tglsfdc · tglsfdc · commit 4c1a1a347a47 · 2022-02-15T17:17:28.000-05:00
Our gcc-on-Solaris buildfarm members emit "incompatible pointer type"
warnings in places where it's not.  This is a bit odd, since AFAICT
Solaris follows the POSIX spec in declaring shmdt's argument as
"const void *", and you'd think any pointer argument would satisfy that.
But whatever.  Part of a general push to remove off-the-beaten-track
warnings where we can easily do so.
diff --git a/src/backend/port/sysv_shmem.c b/src/backend/port/sysv_shmem.c
@@ -289,7 +289,7 @@ static void
 IpcMemoryDetach(int status, Datum shmaddr)
 {
 	/* Detach System V shared memory block. */
-	if (shmdt(DatumGetPointer(shmaddr)) < 0)
+	if (shmdt((void *) DatumGetPointer(shmaddr)) < 0)
 		elog(LOG, "shmdt(%p) failed: %m", DatumGetPointer(shmaddr));
 }
 
@@ -323,7 +323,7 @@ PGSharedMemoryIsInUse(unsigned long id1, unsigned long id2)
 	IpcMemoryState state;
 
 	state = PGSharedMemoryAttach((IpcMemoryId) id2, NULL, &memAddress);
-	if (memAddress && shmdt(memAddress) < 0)
+	if (memAddress && shmdt((void *) memAddress) < 0)
 		elog(LOG, "shmdt(%p) failed: %m", memAddress);
 	switch (state)
 	{
@@ -807,7 +807,7 @@ PGSharedMemoryCreate(Size size,
 				break;
 		}
 
-		if (oldhdr && shmdt(oldhdr) < 0)
+		if (oldhdr && shmdt((void *) oldhdr) < 0)
 			elog(LOG, "shmdt(%p) failed: %m", oldhdr);
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -289,7 +289,7 @@ static void`
`289`	`289`	`IpcMemoryDetach(int status, Datum shmaddr)`
`290`	`290`	`{`
`291`	`291`	`/* Detach System V shared memory block. */`
`292`		`- if (shmdt(DatumGetPointer(shmaddr)) < 0)`
	`292`	`+ if (shmdt((void *) DatumGetPointer(shmaddr)) < 0)`
`293`	`293`	`elog(LOG, "shmdt(%p) failed: %m", DatumGetPointer(shmaddr));`
`294`	`294`	`}`
`295`	`295`
`@@ -323,7 +323,7 @@ PGSharedMemoryIsInUse(unsigned long id1, unsigned long id2)`
`323`	`323`	`IpcMemoryState state;`
`324`	`324`
`325`	`325`	`state = PGSharedMemoryAttach((IpcMemoryId) id2, NULL, &memAddress);`
`326`		`- if (memAddress && shmdt(memAddress) < 0)`
	`326`	`+ if (memAddress && shmdt((void *) memAddress) < 0)`
`327`	`327`	`elog(LOG, "shmdt(%p) failed: %m", memAddress);`
`328`	`328`	`switch (state)`
`329`	`329`	`{`
`@@ -807,7 +807,7 @@ PGSharedMemoryCreate(Size size,`
`807`	`807`	`break;`
`808`	`808`	`}`
`809`	`809`
`810`		`- if (oldhdr && shmdt(oldhdr) < 0)`
	`810`	`+ if (oldhdr && shmdt((void *) oldhdr) < 0)`
`811`	`811`	`elog(LOG, "shmdt(%p) failed: %m", oldhdr);`
`812`	`812`	`}`
`813`	`813`