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

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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 ...
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How to write a very basic compiler

Advanced compilers like gcc compile codes into machine readable files according to the language in which the code has been written (e.g. C, C++, etc). In fact, they interpret the meaning of each codes ...
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Why was the first compiler written before the first interpreter?

The first compiler was written by Grace Hopper in 1952 while the Lisp interpreter was written in 1958 by John McCarthy's student Steve Russell. Writing a compiler seems like a much harder problem than ...
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Why is software OS specific?

I'm trying to determine the technical details of why software produced using programming languages for certain operating systems only work with them. It is my understanding that binaries are specific ...
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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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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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How come compilers are so reliable?

We use compilers on a daily basis as if their correctness is a given, but compilers are programs too, and can potentially contain bugs. I always wondered about this infallible robustness. Have you ...
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Should I use a parser generator or should I roll my own custom lexer and parser code?

What specific advantages and disadvantages of each way to working on a programming language grammar? Why/When should I roll my own? Why/When should I use a generator?
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Are Intel compilers really better than the Microsoft ones? [closed]

Years ago, I was surprised when I discovered that Intel sells Visual Studio compatible compilers. I tried it in particular for C/C++ as well as fantastic diagnostic tools. But the code was simply not ...
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Does an interpreter produce machine code?

I study the topics of compilers and interpreters intensively. I want to check if my base understanding is right, so let's assume the following: I have a language called "Foobish" and its keywords are ...
39
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4answers
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Why doesn't Java have optimization for tail-recursion at all?

From what I have read: The reason is because it is not easy to determine which method will actually be called as we have inheritance. However, why doesn't Java at least have tail-recursion ...
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How safe is it to compile a piece of source code from a random stranger? [closed]

Suppose I'm reviewing code that job applicants send to prove their skills. Clearly I don't want to run executables they send. Not so clearly I'd rather not run the result of compilation of their code ...
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What does “context-free” mean in the term “context-free grammar”?

Given the amount of material that tries to explain what a context-free grammar (CFG) is, I found it surprising that very few (in my sample, less than 1 in 20) give an explanation on why such grammars ...
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10answers
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What is the difference between “Syntax” and “Syntactic Sugar”

Background The Wikipedia page on Syntactic Sugar states: In computer science, syntactic sugar is syntax within a programming language that is designed to make things easier to read or to express. ...
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6answers
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Why does Facebook convert PHP code to C++? [closed]

I read that Facebook started out in PHP, and then to gain speed, they now compile PHP as C++ code. If that's the case why don't they: Just program in c++? Surely there must be SOME errors/bugs when ...
36
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3answers
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How could the first C++ compiler be written in C++?

Stroustrup claims that Cfront, the first C++ compiler, was written in C++ (Stroustrup FAQ). However, how is it even possible that the first C++ compiler be written in C++? The code that makes up the ...
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6answers
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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 ...
31
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5answers
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Is Python Interpreted or Compiled?

This is just a wondering I had while reading about interpreted and compiled languages. Ruby is no doubt an interpreted language, since source code is compiled by an interpreter at the point of ...
30
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6answers
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Why do programs use call stacks, if nested function calls can be inlined?

Why not have the compiler take a program like this: function a(b) { return b^2 }; function c(b) { return a(b) + 5 }; and convert it into a program like this: function c(b) { return b^2 + 5 }; ...
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Can compilers and interpreters have bugs, and what can we (as users) do to deal with them? [closed]

If a compiler's work is essentially translating source code into machine level code, can there be any glitch in a compiler, i.e. a faulty "translation?" The same goes for an interpreter: can it fail ...
27
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3answers
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Why might it be difficult to make a 64 bit version of a program?

In my short time programming, it has been trivial to compile any of my C++, Java, etc. for either a 32 or 64 bit machine so long as I have the full source for the program. But a lot of software is ...
26
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6answers
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What are the caveats of implementing fundamental types (like int) as classes?

When designing and implenting an object-oriented programming language, at some point one must make a choice about implementing fundamental types (like int, float, double or equivalents) as classes or ...
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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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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 ...
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1answer
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What are the main advantages and disadvantages of LL and LR parsing?

When building a parser to a programming language what I earn and what I lost choosing one or the other?
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Are C++ templates just a kind of glorified macros?

From different comparisons among C++ templates and C#/Java generics like this one- ...
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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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Is Google Closure a true compiler?

This question is inspired by the debate in the comments on this Stack Overflow question. The Google Closure Compiler documentation states the following (emphasis added): The Closure Compiler is a ...
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Interpreted vs Compiled: A useful distinction?

A lot of questions get asked here about interpreted vs compiled language implements. I'm wondering whether the distinction actually makes any sense. (Actually the questions are usually about ...
18
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4answers
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Detecting misusage of delete[] vs. delete at compile time

I'd like to know if it's possible to detect the delete error commented below at compile time? Especially, I'd like to hear about g++ compiler. ClassTypeA *abc_ptr = new ClassTypeA[100]; ...
18
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5answers
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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 ...
17
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4answers
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Why doesn't Python need a compiler?

Just wondering (now that I've started with C++ which needs a compiler) why Python doesn't need a compiler? I just enter the code, save it as an exec, and run it. In C++ I have to make builds and all ...
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What came first, the compiler, or the source?

I'm curious about the birth of the compiler. How did programming begin? Did people first build hardware that recognized a certain set of commands, or did people define a language and then build ...
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What is the history of the C compiler?

When we say that "Dennis Ritchie developed C language", do we mean that he has created a compiler (using an 'already' developed other language) which can compile the source code written in C language? ...
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GCC vs clang/LLVM — pros and cons of each [closed]

What are the pros and cons of GCC vs clang/LLVM?
17
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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 ...
17
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4answers
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Why implement a lexer as a 2d array and a giant switch?

I'm slowly working to finish my degree, and this semester is Compilers 101. We're using the Dragon Book. Shortly into the course and we're talking about lexical analysis and how it can be implemented ...
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Why is it so hard to recruit for compiler[-related] jobs? [closed]

Last week, a few colleauges and I were participating in career fairs at three major universities (two here in the US and one in England), where we were trying (without much success) to recruit for ...
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Are there any podcasts (not lectures) about compiler development?

There are several podcasts with lectures from universities. I am looking for "other" podcasts. So are there any non-lecture podcasts about compiler development?
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Why C++ to write a compiler?

I was wondering why C++ is a good choice to write a compiler. Of course C is good for this purpose too, because many compilers are written either in C or C++ but I am more interested in C++ this time. ...
15
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Does Scrum make sense when implementing a new compiler backend?

I have an existing language that I need to port to a new platform. I'll probably attempt this by changing the backend of the existing compiler. It is a significant amount of work to re-write the ...
15
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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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Why can't native machine code be easily decompiled?

With bytecode-based virtual machine languages like Java, VB.NET, C#, ActionScript 3.0, etc., you hear sometimes about how easy it is to just go download some decompiler off the Internet, run the ...
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9answers
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Career advice: PhD in theory of programming languages [closed]

I'm very interested in the theories of programming languages and going to apply a PhD in this topic, but I want to know more about the career after the graduate education. besides being a professor, ...
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Why would more CPU cores on virtual machine slow compile times?

[edit#2] If anyone from VMWare can hit me up with a copy of VMWare Fusion, I'd be more than happy to do the same as a VirtualBox vs VMWare comparison. Somehow I suspect the VMWare hypervisor will be ...
13
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13answers
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Is it true that first versions of C compilers ran for dozens of minutes and required swapping floppy disks between stages?

Inspired by this question. I heard that some very very early versions of C compilers for personal computers (I guess it's around 1980) resided on two or three floppy disks and so in order to compile ...
13
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2answers
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What does scannerless parsing have to do with the “Dangling Else Problem”?

I do not understand this sentence from the Wikipedia article on the Dangling Else problem: [The Dangling Else problem] is a problem that often comes up in compiler construction, especially ...
13
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How compilers know about other classes and their properties?

I'm writing my first programming language that is object orientated and so far so good with create a single 'class'. But, let's say I want to have to classes, say ClassA and ClassB. Provided these ...
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When to pay for C++ compilers [closed]

Recently I have began to wonder when developers should pay for compilers. Compilers come for free with most platforms or there is a free version easily obtainable. Example: OS X - GCC and Clang/LLVM ...
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12answers
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Are there any compilers that attempt to fix syntax errors on their own? [closed]

I heard a while back that there used to be a compiler that attempted to fix syntax errors by analyzing context and inferring what was intended. Does such a compiler really exist? Obviously it has ...