Initialize output parameter of spvtools::LookupOperand (KhronosGroup#6223)

Author: jan-kelemen

source/binary.cpp

@@ -856,7 +856,7 @@ void Parser::recordNumberType(size_t inst_offset,
       info.type = SPV_NUMBER_FLOATING;
       info.bit_width = peekAt(inst_offset + 2);
       if (inst->num_words >= 4) {
-        const spvtools::OperandDesc* desc;
+        const spvtools::OperandDesc* desc = nullptr;
         spv_result_t status = spvtools::LookupOperand(
             SPV_OPERAND_TYPE_FPENCODING, peekAt(inst_offset + 3), &desc);
         if (status == SPV_SUCCESS) {

source/text_handler.cpp

@@ -336,7 +336,7 @@ spv_result_t AssemblyContext::recordTypeDefinition(
       return diagnostic() << "Invalid OpTypeFloat instruction";
     spv_fp_encoding_t enc = SPV_FP_ENCODING_UNKNOWN;
     if (pInst->words.size() >= 4) {
-      const spvtools::OperandDesc* desc;
+      const spvtools::OperandDesc* desc = nullptr;
       spv_result_t status = spvtools::LookupOperand(SPV_OPERAND_TYPE_FPENCODING,
                                                     pInst->words[3], &desc);
       if (status == SPV_SUCCESS) {

source/val/validate_type.cpp

@@ -140,7 +140,7 @@ spv_result_t ValidateTypeFloat(ValidationState_t& _, const Instruction* inst) {
       return _.diag(SPV_ERROR_INVALID_DATA, inst)
              << "8-bit floating point type requires an encoding.";
     }
-    const spvtools::OperandDesc* desc;
+    const spvtools::OperandDesc* desc = nullptr;
     const std::set<spv::FPEncoding> known_encodings{
         spv::FPEncoding::Float8E4M3EXT, spv::FPEncoding::Float8E5M2EXT};
     spv_result_t status = spvtools::LookupOperand(SPV_OPERAND_TYPE_FPENCODING,