fix(pag): Incorrect calculation of last used page when database contains only one PIP (#8949)

TreeHunter9 · Artyom Ivanov · dyemanov · commit 8afaeaeb3431 · 2026-03-24T12:25:59.000+03:00
Co-authored-by: Artyom Ivanov &lt;artyom.ivanov@red-soft.ru&gt;
diff --git a/src/jrd/pag.cpp b/src/jrd/pag.cpp
@@ -2318,7 +2318,9 @@ ULONG PageSpace::lastUsedPage()
 	CCH_RELEASE(tdbb, &window);
 	pipMaxKnown = pipLast;
 
-	return last_bit + 1 + (pipLast == pipFirst ? 0 : pipLast);
+	if (pipLast == pipFirst)
+		return last_bit > 0 ? last_bit : 0;
+	return pipLast + last_bit + 1;
 }
 
 ULONG PageSpace::lastUsedPage(const Database* dbb)

Original file line number	Diff line number	Diff line change
`@@ -2318,7 +2318,9 @@ ULONG PageSpace::lastUsedPage()`
`2318`	`2318`	`CCH_RELEASE(tdbb, &window);`
`2319`	`2319`	`pipMaxKnown = pipLast;`
`2320`	`2320`
`2321`		`- return last_bit + 1 + (pipLast == pipFirst ? 0 : pipLast);`
	`2321`	`+ if (pipLast == pipFirst)`
	`2322`	`+ return last_bit > 0 ? last_bit : 0;`
	`2323`	`+ return pipLast + last_bit + 1;`
`2322`	`2324`	`}`
`2323`	`2325`
`2324`	`2326`	`ULONG PageSpace::lastUsedPage(const Database* dbb)`