private boolean parseFunctionDefinition() {

			functionDefinition = null;

			try {
				functionDefinition = parseSignature();
			}
			catch (CancelledException e) {
				// ignore
			}

			if (functionDefinition == null) {
				return false;
			}

			functionDefinition.setNoReturn(hasNoReturnSelected());

			try {
				functionDefinition.setCallingConvention(getCallingConvention());
			}
			catch (InvalidInputException e) {
				// should not occur since dialog restricts calling convention choice
			}

			return true;
		}
Construct signature override for called function
@param tool active tool
@param func function from which program access is achieved and supply of preferred 
datatypes when parsing signature
@param signature initial prototype signature to be used
@param conv initial calling convention
Ghidra/Features/Decompiler/src/main/java/ghidra/app/plugin/core/decompile/actions/OverridePrototypeAction.java