Bug 1295835 - Address some compilation maybe-uninitialized warnings. r=luke

--HG--
extra : rebase_source : 7842fdd361939aba7248cdc463dd54e41a3162ea

js/src/asmjs/AsmJS.cpp

@@ -2478,7 +2478,7 @@ ExtractSimdValue(ModuleValidator& m, ParseNode* pn)
 {
     MOZ_ASSERT(IsSimdLiteral(m, pn));
 
-    SimdType type;
+    SimdType type = SimdType::Count;
     JS_ALWAYS_TRUE(IsSimdTuple(m, pn, &type));
     MOZ_ASSERT(CallArgListLength(pn) == GetSimdLanes(type));
 

js/src/asmjs/WasmBaselineCompile.cpp

@@ -3205,7 +3205,7 @@ class BaseCompiler
 # if defined(JS_CODEGEN_X64)
         Operand dstAddr(HeapReg, ptr.reg, TimesOne, access.offset());
 
-        Register intReg;
+        Register intReg = Register::Invalid();
         if (src.tag == AnyReg::I32)
             intReg = src.i32().reg;
         else if (src.tag == AnyReg::I64)

js/src/asmjs/WasmBinary.h

@@ -891,7 +891,7 @@ class Decoder
         return uncheckedReadVarU<uint32_t>();
     }
     int32_t uncheckedReadVarS32() {
-        int32_t i32;
+        int32_t i32 = 0;
         MOZ_ALWAYS_TRUE(readVarS32(&i32));
         return i32;
     }
@@ -899,7 +899,7 @@ class Decoder
         return uncheckedReadVarU<uint64_t>();
     }
     int64_t uncheckedReadVarS64() {
-        int64_t i64;
+        int64_t i64 = 0;
         MOZ_ALWAYS_TRUE(readVarS64(&i64));
         return i64;
     }

js/src/asmjs/WasmBinaryIterator.h

@@ -793,7 +793,7 @@ ExprIter<Policy>::readElse(ExprType* thenType, Value* thenValue)
 {
     MOZ_ASSERT(Classify(expr_) == ExprKind::Else);
 
-    ExprType type;
+    ExprType type = ExprType::Limit;
     LabelKind kind;
     if (!popControl(&kind, &type, thenValue))
         return false;
@@ -826,7 +826,7 @@ ExprIter<Policy>::readEnd(LabelKind* kind, ExprType* type, Value* value)
 {
     MOZ_ASSERT(Classify(expr_) == ExprKind::End);
 
-    LabelKind validateKind;
+    LabelKind validateKind = static_cast<LabelKind>(-1);
     ExprType validateType;
     if (!popControl(&validateKind, &validateType, value))
         return false;

js/src/asmjs/WasmBinaryToAST.cpp

@@ -1333,7 +1333,7 @@ AstDecodeImportSection(AstDecodeContext& c)
         return AstDecodeFail(c,  "too many imports");
 
     for (uint32_t i = 0; i < numImports; i++) {
-        AstImport* import;
+        AstImport* import = nullptr;
         if (!AstDecodeImport(c, i, &import))
             return false;
         if (!c.module().append(import))
@@ -1495,7 +1495,7 @@ AstDecodeExportSection(AstDecodeContext& c)
         return AstDecodeFail(c, "too many exports");
 
     for (uint32_t i = 0; i < numExports; i++) {
-        AstExport* export_;
+        AstExport* export_ = nullptr;
         if (!AstDecodeFunctionExport(c, &export_))
             return false;
         if (!c.module().append(export_))

js/src/asmjs/WasmCompile.cpp

@@ -183,7 +183,7 @@ static bool
 DecodeBrTable(FunctionDecoder& f)
 {
     uint32_t tableLength;
-    ExprType type;
+    ExprType type = ExprType::Limit;
     if (!f.iter().readBrTable(&tableLength, &type, nullptr, nullptr))
         return false;
 

js/src/asmjs/WasmTextToBinary.cpp

@@ -1555,7 +1555,7 @@ ParseNaNLiteral(const char16_t* cur, const char16_t* end, Float* result)
             return false;
         CheckedInt<Bits> u = 0;
         do {
-            uint8_t digit;
+            uint8_t digit = 0;
             MOZ_ALWAYS_TRUE(IsHexDigit(*cur, &digit));
             u *= 16;
             u += digit;