seems that there is still a way to leave MtmLockCount uncleaden upon error. Comment out assertion for now.

kelvich · kelvich · commit cff9b21dc30a · 2018-01-29T18:22:09.000+03:00
diff --git a/multimaster.c b/multimaster.c
@@ -369,7 +369,7 @@ void MtmLock(LWLockMode mode)
 		}
 #endif
 		if (mode == LW_EXCLUSIVE) {
-			Assert(MtmLockCount == 0);
+			// Assert(MtmLockCount == 0);
 			Assert(MyProcPid != 0);
 			Mtm->lastLockHolder = MyProcPid;
 			Assert(MyProcPid);

Original file line number	Diff line number	Diff line change
`@@ -369,7 +369,7 @@ void MtmLock(LWLockMode mode)`
`369`	`369`	`}`
`370`	`370`	`#endif`
`371`	`371`	`if (mode == LW_EXCLUSIVE) {`
`372`		`- Assert(MtmLockCount == 0);`
	`372`	`+ // Assert(MtmLockCount == 0);`
`373`	`373`	`Assert(MyProcPid != 0);`
`374`	`374`	`Mtm->lastLockHolder = MyProcPid;`
`375`	`375`	`Assert(MyProcPid);`