Fix error in parser

Fix bug when processing sections and trying to read ahead for locals in source code.

Signed-off-by: Ádám László Kulcsár <[email protected]>

src/parser/WASMParser.cpp

@@ -1286,7 +1286,7 @@ class WASMBinaryReader : public wabt::WASMBinaryReaderDelegate {
 
     size_t computeExprResultPosition(Walrus::Value::Type type)
     {
-        if (!m_preprocessData.m_inPreprocess) {
+        if (!m_preprocessData.m_inPreprocess && !m_localInfo.empty()) {
             // if there is local.set code ahead,
             // we can use local variable position as expr target position
             auto localSetInfo = readAheadLocalGetIfExists();

test/basic/read_ahead_fix.wast

@@ -0,0 +1,43 @@
+(module
+  (func $some_func)
+  (table 514 514 funcref)
+  (elem (i32.const 1) func
+    $0 $1 $2 $3 $4 $5 $6 $7 $8 $9 $10 $11 $12 $13 $14 $15 $16 $17 $18 $19 $20 $21 $22 $23 $24 $25 $26 $27 $28 $29 $30 $31 $32 $33
+  )
+
+  (func $0)
+  (func $1)
+  (func $2)
+  (func $3)
+  (func $4)
+  (func $5)
+  (func $6)
+  (func $7)
+  (func $8)
+  (func $9)
+  (func $10)
+  (func $11)
+  (func $12)
+  (func $13)
+  (func $14)
+  (func $15)
+  (func $16)
+  (func $17)
+  (func $18)
+  (func $19)
+  (func $20)
+  (func $21)
+  (func $22)
+  (func $23)
+  (func $24)
+  (func $25)
+  (func $26)
+  (func $27)
+  (func $28)
+  (func $29)
+  (func $30)
+  (func $31)
+  (func $32)
+  (func $33)
+)
+