A compiler is a computer program that transforms source code written in one programming language into another computer language.

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How does Chrome V8 work? And why was JavaScript not JIT-Compiled in the first place?

I have been researching Interpreters/Compilers, then I stumbled across JIT-Compilation - specifically Google Chrome's V8 Javascript Engine. My questions are - How can it be faster than standard ...
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1answer
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Security error on asp.net system after deployment of bug fix dll

I (recently inherited) a asp.net web application in production. After fixing a generic bug in the area of making a table selection - we have a problem regarding security policies not allowing access ...
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6answers
335 views

“Write an Assembler in C.” Why writing a machine code translator for a low level language in a higher level language?

My Microprocessor class instructor gave us an assignment and said: "Write an Assembler in C." - My beloved Professor So it seemed a little bit illogical to me. If I'm not wrong Assembly ...
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2answers
654 views

What semantic features of Python (and other dynamic languages) contribute to its slowness?

I don't know very well Python. I'm trying to understand more precisely what exact features of dynamic languages (à la Python, Lua, Scheme, Perl, Ruby, ....) are forcing their implementations to be ...
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1answer
1k views

High-level language to assembly

If assembly language is only a readable way to represent machine code, then why are HLLs converted to assembly first and then to machine code? Shouldn't HLLs be directly converted to machine code?
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Origin of the native compiler [duplicate]

I have been using GCC in a nix environment for as long as I remember. Given the wide range of processors, such as those from Atmel, ARM, Intel, and possibly a custom-made soft-core on an FPGA, and ...
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204 views

Is C is a portable language for new architecture or it is specific for ISA?

How C language is portable to any instruction set (I mean for new architecture). Do we have to write again C compiler for new architecture?
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1answer
99 views

How to resolve generic typenames in compiler?

Let's say I have such code (and its meaning is like in C#): class Foo<T> { public T my_field; } and later in code I have: var foo = new Foo<int>(); foo.my_field = 5; My problem ...
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How do I know if the compiler broke my code and what do I do if it was the compiler?

Once in a while C++ code will not work when compiled with some level of optimization. It may be compiler doing optimization that breaks the code or it may be code containing undefined behavior which ...
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10answers
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Is Ken Thompson's compiler hack still a threat?

Ken Thompson Hack (1984) Ken Thompson outlined a method for corrupting a compiler binary (and other compiled software, like a login script on a *nix system) in 1984. I was curious to know if modern ...
5
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1answer
94 views

Do I need to declare a delay timer variable as volatile even if I access it from another module

This is a question more about using volatile to prevent optimization than about caching write/read of a variable. Particularly timer delay variables since I don't want to declare everything volatile ...
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2answers
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Do compilers utilize multithreading for faster compile times?

If I remember my compilers course correctly, the typical compiler has the following simplified outline: A lexical analyzer scans (or calls some scanning function) the source code character-by-...
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How do JIT interpreters handle variable names?

Let's say I am to design a JIT interpreter that translates IL or bytecode to executable instructions at runtime. Every time a variable name is encountered in the code, the JIT interpreter has to ...
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9answers
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Why are self-hosting compilers considered a rite of passage for new languages?

I've heard in a number of places now that people expect languages to use, or at least have, a self-hosting compiler in order to deserve respect. I'm curious as to why this is. A compiler seems like a ...
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4answers
2k views

GCC vs clang/LLVM — pros and cons of each [closed]

What are the pros and cons of GCC vs clang/LLVM?
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3answers
8k views

How do we go from assembly to machine code(code generation)

Is there an easy way to visualize the step between assembling code to machine code? For example if you open about a binary file in notepad you see a textually formatted representation of machine code....
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4answers
545 views

Why isn't there a primitive “complex number” type in Java?

Does anyone know why something like http://www.ipd.uka.de/JavaParty/cj/#Down was never completed and integrated into mainline java? This seems like a no-brainer... I realize the java gawds dont want ...
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0answers
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How to get verification that you've implemented all your API in a static library?

I just learned that static library building skips the linking stage, which explains why my build process succeeds all the time when it's possible I actually haven't implemented a function in my header....
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Why isn't the overloading with return types allowed? (at least in usually used languages)

I don't know about all programming languages, but it's clear that usually the possibility of overloading a method taking into consideration its return type (assuming its arguments are the same number ...
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Why do some compilers generate direct machine code?

I was taking this course - CMU 18-447, Computer Architecture at Carnegie Mellon to brush my knowledge and concepts. They say that most of the machine level details and implementations are taken care ...
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5answers
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JIT compiler for C, C++, and the likes

Is there any just-in-time compiler out there for compiled languages, such as C and C++? (The first names that come to mind are Clang and LLVM! But I don't think they currently support it.) ...
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3answers
190 views

Are browser console errors 'compiler errors', 'runtime errors', or neither?

I was trying to communicate with a coworker about a JavaScript error I was being notified about in my browser's console window when I realized that I wasn't sure if I should refer to this as a ...
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1answer
68 views

Self-compilation in Forth

What is Self-compilation (a.k.a. Meta-compilation) in Forth? How it works and why is it useful? Does it have any practical usage and is it still used in modern systems?
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Why was the Itanium processor difficult to write a compiler for?

It's commonly stated that Intel's Itanium 64-bit processor architecture failed because the revolutionary EPIC instruction set was very difficult to write a good compiler for, which meant a lack of ...
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3answers
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In which process does syntax error occur? (tokenizing or parsing)

I'm trying to understand compilation and interpretation, step by step figuring out a total image. So I came up to a question while reading http://www.cs.man.ac.uk/~pjj/farrell/comp3.html this article ...
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How exactly is an Abstract Syntax Tree created?

I think I understand the goal of an AST, and I've built a couple of tree structures before, but never an AST. I'm mostly confused because the nodes are text and not number, so I can't think of a nice ...
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How to report multiple errors as a result of validation?

I have a class that transforms a complex model, for example an abstract syntax tree or intermediate model. The model can be either valid, invalid or partially invalid, i.e. it contains errors but some ...
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Do some built-in functions loop behind the scenes?

I mostly code in C# & VB, but I think this question is pretty universal. I try to limit loops to increase performance. For instance, string functions that split the string into an array, or do a ...
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260 views

Trust .net compiler after Microsoft updates

Microsoft releases upgrades and changes to .net, msbuild and Visual Studio quite frequently. How can I be sure the MSIL code created by msbuild or the Roslyn compiler in VS 2015 will be the same or ...
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2answers
78 views

Testing strategies for interpreter language parser

For a recent personal project, I started working on an interpreter for my own programming language. One of the ground rules I set for myself on this project is that I need to properly test as much of ...
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4answers
884 views

How can I implement an 'if' statement in an interpreter?

If I were writing a compiler (say for a stack-based VM), the code for an if statement: if (<some_expression>) { <some_instructions> } Would be translated to the following psuedo-...
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2answers
417 views

How to reduce size of jar file?

I dont know how to reduce the size of jar file. When we normally code in Java Swing the jar file is created, is there any way to reduce the size of jar file? I can't remove the images and other stuff ...
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Why isn't there a python compiler to native machine code?

As I understand, the cause of the speed difference between compiled languages and python is, that the first compiles code all way to the native machine's code, whereas python compiles to python ...
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1answer
103 views

Compiler design prevent register override

I'm trying to write a compiler for a self-designed CPU with accompanying instruction set. The CPU has 3 registers, 2 input registers (B and C) and one output register (D). When for example an ADD ...
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When to use ANTLR and when to use a parsing library

I've always wanted to learn how to write a compiler - I've decided to use ANTLR, and am currently reading through the book (its very good by the way) I'm pretty new to this, so go easy, but the jist ...
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1answer
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Are there compilers which optimize the use of mathematical functions?

Today while programming I stumbled upon the following question - are there any compilers which optimize based on mathematical assumptions? For instance in cases like unsigned int i,b; (i,b not ...
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2answers
395 views

Is it possible to implement a native compiler for a 'managed language' such as Java?

In most cases, it is possible to create both a native compiler and an interpreter for a programming language. The compiler would simply convert the source code to machine code, and the interpreter ...
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1answer
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Why does the documentation on some languages say “equivalent to” rather than “is”?

Why does the documentation on some languages say "equivalent to" rather than "is"? For example, the Python Docs say itertools.chain(*iterables) ... Equivalent to: def chain(*iterables):...
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Is there a standard way or standard alternative to packing a struct in c?

When programming in C I have found it invaluable to pack structs using GCCs __attribute__((__packed__)) attribute so I can easily convert a structured chunk of volatile memory to an array of bytes to ...
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2answers
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JIT based on precompiled code templates

This is a crazy idea that I just came up with, and I'm interested in knowing if it would be workable, or if someone already wrote about or implemented it. Imagine you are on a platform (a game ...
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1answer
130 views

Is an AST enough to build any translator? [closed]

Note: In my ignorance of the difference between Programmers vs StackOverflow sites (which I know now), I had posted this question on StackOverflow earlier. What I'm looking for is some elaboration, ...
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Why are there so few C compilers?

C is one of the most widely-used languages in the world. It accounts for a huge proportion of existing code and continues to be used for a vast amount of new code. It's beloved by its users, it's so ...
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3answers
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What is benefit that a compiler is implemented in the same language it compiles? [duplicate]

I've seen it's very common for a compiler to be made in the language it's compiling. What is the benefit of this? Seems like it makes the process for outsiders (and the developers for a while) more ...
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8answers
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How can we be certain that the lower components of computer programming like compilers, assemblers, machine instructions, etc. are flawless?

Since we are becoming more and more reliant on computing, including very critical tasks of day-to-day life, I was just wondering how those vital components are tested. More technically, how are the ...
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When does it make sense to compile my own language to C code first?

When designing an own programming language, when does it make sense to write a converter that takes the source code and converts it to C or C++ code so that I can use an existing compiler like gcc to ...
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1answer
204 views

How do I create my own Objective-C to Swift converter? [closed]

I'm really interested in writing my own converter. I know C++/Python/Objective-C/Swift and a little Haskell. There are website like objectivec2swift and iswift.org, which can convert OC to Swift ...
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1answer
226 views

Single import in a large file vs. multiple imports in smaller files. [Golang]

I'm sure the folks at Google worked long and hard to ensure the programmer wouldn't have to worry about details like this, but I'm curious. In Go if I have multiple files in the same package, but ...
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2answers
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What is ASM.js and what does it mean for everyone?

I'm starting to hear rumblings about this project called ASM.js. Currently their web site is terrible and confusing. Here's what I know from my research on the web. It is a subset of JavaScript that ...
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0answers
379 views

Writing a Compiler - .reloc section of the COFF

I'm looking for a little bit of direction in writing a compiler. I've written in Common Intermediate Language, C#, and various other .NET languages; I've written my own Metadata Parser and now I'm ...
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How are individual lines of code and functions stored in a Concrete Syntax Tree?

I'm trying to write a simple compiler for learning purposes. I've been reading the Dragon Book and Modern Compiler Design and one part I don't understand is how the Concrete Syntax Tree is actually ...