19-12-2012, 06:06 PM
Debuggers
Debuggers.doc (Size: 612.5 KB / Downloads: 28)
What is a Syntax Error?
• The main aim of an error is to find mistakes in a given object deck.
• The syntax error deals with mistakes occurred during syntax phase or lexical analysis phase of the compiler.
• These mistakes are generally occurred due to wrong words or misspelled patterns of sentences, which results to improper identifiers.
• For example:
What is a Semantic Error?
• The main task of an error is to find errors in a given object deck.
• The semantic errors are detectable during compilation process.
• The semantic word generally refers to meaning a line of code.
• Therefore any construct that have right syntactic structure, but no meaning to involved operation will show semantic error.
Absolute loaders:
• In case of absolute loaders, the loader performs the function, of loading the object program from secondary input into the main memory for execution.
• The assembler places the object source code on cards, then it generates the address and relocation information from loader.
• The various advantages and disadvantages for absolute loaders are as follows
Advantages:
(i) The absolute loaders are very much simple to implement and use.
(ii) The absolute loaders make core available to user. It is due to reason that the assembler is not in memory during load time.
Disadvantages:
(i) The developer has to remember the address subroutines to be used in subroutine linkage.
(ii) The developer has to specify the address to load the program.