AIX: Fix 'may be used uninitialized' compiler errors.

src/wasm/asm-wasm-builder.cc

 // 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.
 
 #include "src/v8.h"
 
 // Required to get M_E etc. in MSVC.
 #if defined(_WIN32)
 #define _USE_MATH_DEFINES
 #endif
@@ skipping 449 matching lines @@
     }
   }
 
   void VisitLiteral(Literal* expr) {
     Handle<Object> value = expr->value();
     if (!in_function_ || !value->IsNumber()) {
       return;
     }
     Type* type = expr->bounds().upper;
     if (type->Is(cache_.kAsmSigned)) {
-      int32_t i;
+      int32_t i = 0;
       if (!value->ToInt32(&i)) {
         UNREACHABLE();
       }
       byte code[] = {WASM_I32V(i)};
       current_function_builder_->EmitCode(code, sizeof(code));
     } else if (type->Is(cache_.kAsmUnsigned) || type->Is(cache_.kAsmFixnum)) {
-      uint32_t u;
+      uint32_t u = 0;
       if (!value->ToUint32(&u)) {
         UNREACHABLE();
       }
       int32_t i = static_cast<int32_t>(u);
       byte code[] = {WASM_I32V(i)};
       current_function_builder_->EmitCode(code, sizeof(code));
     } else if (type->Is(cache_.kAsmDouble)) {
       double val = expr->raw_value()->AsNumber();
       byte code[] = {WASM_F64(val)};
       current_function_builder_->EmitCode(code, sizeof(code));
@@ skipping 1045 matching lines @@
 // that zone in constructor may be thrown away once wasm module is written.
 WasmModuleIndex* AsmWasmBuilder::Run() {
   AsmWasmBuilderImpl impl(isolate_, zone_, literal_, foreign_, typer_);
   impl.Compile();
   WasmModuleWriter* writer = impl.builder_->Build(zone_);
   return writer->WriteTo(zone_);
 }
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8