[wasm] Errors in names section do not fail the whole module.

src/wasm/decoder.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_WASM_DECODER_H_
 #define V8_WASM_DECODER_H_
 
 #include <memory>
 
 #include "src/base/compiler-specific.h"
@@ skipping 19 matching lines @@
 // A helper utility to decode bytes, integers, fields, varints, etc, from
 // a buffer of bytes.
 class Decoder {
  public:
   Decoder(const byte* start, const byte* end)
       : start_(start),
         pc_(start),
         end_(end),
         error_pc_(nullptr),
         error_pt_(nullptr) {}
+  Decoder(const byte* start, const byte* pc, const byte* end)
+      : start_(start),
+        pc_(pc),
+        end_(end),
+        error_pc_(nullptr),
+        error_pt_(nullptr) {}
 
   virtual ~Decoder() {}
 
   inline bool check(const byte* base, unsigned offset, unsigned length,
                     const char* msg) {
     DCHECK_GE(base, start_);
     if ((base + offset + length) > end_) {
       error(base, base + offset, "%s", msg);
       return false;
     }
@@ skipping 127 matching lines @@
     return consume_leb<uint32_t, false>(name);
   }
 
   // Reads a LEB128 variable-length signed 32-bit integer and advances {pc_}.
   int32_t consume_i32v(const char* name = nullptr) {
     return consume_leb<int32_t, true>(name);
   }
 
   // Consume {size} bytes and send them to the bit bucket, advancing {pc_}.
   void consume_bytes(uint32_t size, const char* name = "skip") {
-    TRACE("  +%d  %-20s: %d bytes\n", static_cast<int>(pc_ - start_), name,
-          size);
+#if DEBUG
+    if (name) {
+      // Only trace if the name is not null.
+      TRACE("  +%d  %-20s: %d bytes\n", static_cast<int>(pc_ - start_), name,
+            size);
+    }
+#endif
     if (checkAvailable(size)) {
       pc_ += size;
     } else {
       pc_ = end_;
     }
   }
 
   // Check that at least {size} bytes exist between {pc_} and {end_}.
   bool checkAvailable(int size) {
     intptr_t pc_overflow_value = std::numeric_limits<intptr_t>::max() - size;
@@ skipping 190 matching lines @@
     return traceOffEnd<uint32_t>();
   }
 };
 
 #undef TRACE
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_DECODER_H_