erigontech · AskAlexSharov · Aug 13, 2026 · Aug 4, 2026 · Aug 4, 2026 · Aug 5, 2026
@@ -21,7 +21,6 @@ import (
 	"slices"
 
 	"github.com/erigontech/erigon/common"
-	"github.com/erigontech/erigon/common/dbg"
 	"github.com/erigontech/erigon/common/hexutil"
 	"github.com/erigontech/erigon/execution/protocol/params"
 	"github.com/erigontech/erigon/execution/types"
@@ -37,8 +36,8 @@ const (
 	maxLogBytesPerTxn = int(params.MaxTxnGasLimit / params.LogDataGas) // 2MB
 
 	// Fractions of those, because the pool never shrinks: the whole ceiling would
-	// park 13MB of entries per arena, while a tenth still holds the p99 block of
-	// 1706 logs that a caller resetting per block pools in one go.
+	// park 13MB of entries per arena, while a tenth still holds the ~1700 logs of
+	// a p99 block that a caller resetting per block pools in one go.
 	maxPooledLogEntries = maxLogsPerTxn / 10
 	maxPooledLogBytes   = maxLogBytesPerTxn / 2
 
@@ -49,7 +48,7 @@ const (
 
 	// Slots the arena keeps between resets. The run is a block for a caller that
 	// resets per block, so this is bounded by the memory it costs rather than by
-	// a transaction's budget: 32KB of pointers, holding the p99 block of 1706.
+	// a transaction's budget: 32KB of pointers, holding a p99 block's ~1700.
 	maxRetainedLogSlots = 32 * 1024 / 8
 )
 
@@ -150,14 +149,15 @@ func (a *logArena) revertLast(txIndex int) {
 }
 
 // forTx returns the entries txIndex emitted, owned by the arena. They are held
-// in one run rather than grouped, and a transaction's own are the tail of it,
-// so any other transaction reads as empty.
+// in one run rather than grouped, and a transaction's own are the tail of it, so
+// a transaction newer than the tail reads as empty and an older one panics.
-// in one run rather than grouped, and a transaction's own are the tail of it, so
-// a transaction newer than the tail reads as empty and an older one panics.
+// in one run rather than grouped, and a transaction's own are the tail of it, so
+// a transaction newer than the tail reads as empty and an older one panics
+// while the run still holds a newer entry.
-// in one run rather than grouped, and a transaction's own are the tail of it, so
-// a transaction newer than the tail reads as empty and an older one panics.
+// in one run rather than grouped, and a transaction's own are the tail of it, so
+// a transaction newer than the tail reads as empty and an older one panics
+// while the run still holds a newer entry.
 func (a *logArena) forTx(txIndex int) types.Logs {
 	entries := a.entries
 	i := len(entries)
-	if dbg.AssertEnabled && i > 0 && txIndex < int(entries[i-1].TxIndex) {
+	if i > 0 && txIndex < int(entries[i-1].TxIndex) {
 		// Newer than the tail is a transaction that emitted nothing, which is
-		// how most of them end. Older is a caller reading what it has left.
+		// how most of them end. Older is a caller reading what it has left:
+		// answering empty would read as "emitted no logs", so say so instead.
 		panic(fmt.Sprintf("logs of tx %d asked for, the run has reached tx %d",
 			txIndex, int(entries[i-1].TxIndex)))
 	}

@@ -655,12 +655,11 @@ func TestLogIndexIsBlockWide(t *testing.T) {
 	require.Equal(t, hexutil.Uint(0), ibs.GetRawLogs(0)[0].Index, "next block restarts at zero")
 }
 
-// Reading a transaction the run has moved past answers empty, which a receipt
-// records as "emitted no logs". A transaction that simply emitted nothing is
-// newer than the tail, not older, so it stays legal.
-func TestGetLogsOfPastTxAsserts(t *testing.T) {
-	defer func(prev bool) { dbg.AssertEnabled = prev }(dbg.AssertEnabled)
-	dbg.AssertEnabled = true
+// Reading a transaction the run has moved past would answer empty, which a
+// receipt records as "emitted no logs" - so it panics instead. A transaction that
+// simply emitted nothing is newer than the tail, not older, so it stays legal.
+func TestGetLogsOfPastTxPanics(t *testing.T) {
+	t.Parallel()
 
 	ibs := New(nil)
 	ibs.SetTxContext(1, 0)
@@ -673,6 +672,20 @@ func TestGetLogsOfPastTxAsserts(t *testing.T) {
 	require.Panics(t, func() { ibs.GetRawLogs(0) }, "the run has moved past tx 0")
 }
 
+// The past-transaction check guards production, not just assert builds: a caller
+// that reads what the run has left must not be handed the tail's logs as if they
+// were its own. Not parallel - it writes the global assert flag.
-// The past-transaction check guards production, not just assert builds: a caller
-// that reads what the run has left must not be handed the tail's logs as if they
-// were its own. Not parallel - it writes the global assert flag.
+// The past-transaction check guards production, not just assert builds: a caller
+// that reads what the run has left would otherwise be answered empty, which a
+// receipt records as "emitted no logs". Not parallel - it writes the global
+// assert flag.
-// The past-transaction check guards production, not just assert builds: a caller
-// that reads what the run has left must not be handed the tail's logs as if they
-// were its own. Not parallel - it writes the global assert flag.
+// The past-transaction check guards production, not just assert builds: a caller
+// that reads what the run has left would otherwise be answered empty, which a
+// receipt records as "emitted no logs". Not parallel - it writes the global
+// assert flag.
+func TestGetLogsOfPastTxPanicsWithoutAsserts(t *testing.T) {
+	defer func(prev bool) { dbg.AssertEnabled = prev }(dbg.AssertEnabled)
+	dbg.AssertEnabled = false
+
+	ibs := New(nil)
+	ibs.SetTxContext(1, 3)
+	ibs.AddLog(&types.Log{Address: common.HexToAddress("0x1")})
+
+	require.Panics(t, func() { ibs.GetRawLogs(2) }, "tx 2 is older than the tail")
+}
+
 // Whatever the traffic looks like, one arena holds a bounded amount: the pool,
 // and the one array the run left behind. This is the invariant a shape-specific
 // leak breaks — logs parked per tx index, an array kept because one block was