A compiler is a computer program (or set of programs) that transforms source code written in a programming language (the source language) into another computer language (the target language, often having a binary form known as object code).

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488 views

Does a prose to code compiler exist? [closed]

I have seen some horrible code in my time including people virtually duplicating the code in comments // add 4 to x x+=4; // for each i in 0 to 9 for (int i = 0; i < 10; i++) { // multiply x ...
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2answers
410 views

C++ Without Source Files

Bjarne Stroustrup mentions in his book "The C++ Programming Language, 4th Edition" that not all C++ implementations use files to store and compile code: There are systems that do not store, ...
4
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4answers
991 views

How does Python compile some its code in C?

I read that some constructs of Python are more efficient because they are compiled in C. https://wiki.python.org/moin/PythonSpeed/PerformanceTips Some of the examples used were map() and filter(). I ...
3
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3answers
405 views

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 ...
32
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5answers
2k views

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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2answers
126 views

Does a custom scripting language require it's own compiler/assembler? [closed]

Or is the script generally converted to a known language such as C++ first? And how generally to you integrate a scripting language with the say a game engine?
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2answers
283 views

Writing a superset of a programming language as a transcompiler

My idea is to write a superset of C# (but question is not language-specific), so that it source-to-source compiles (transcompiles) to C# itself (fall-through switch clauses, default method parameters ...
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4answers
989 views

Writing a new programming language - when and how to bootstrap datastructures?

I'm in the process of writing my own programming language which, thus far, has been going great in terms of what I set out to accomplish. However, now, I'd like to bootstrap some pre-existing data ...
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1answer
133 views

Coding shortcuts for type conversions or similar [closed]

bool? example = null; is actually Nullable<System.Boolean> example = null; Now for the bool to System.Boolean conversion or actually compile-time replacement: We ususally hardly care, as it ...
3
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1answer
203 views

Compiler warnings and errors [duplicate]

I come from a C# background before my existing role. I am developing a VB.NET app. The code I inherited had option strict set to off and all other directives set to 'None'. I have recently switched ...
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9answers
808 views

Compiler Warnings

Many compilers have warning messages to warn the programmers about potential runtime, logic and performance errors, most times, you quickly fix them, but what about unfixable warnings? How do you ...
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1answer
48 views

How to keep AST for feature access?

Consider such code (let's say it is C++) Foo::Bar.get().X How one should keep the AST for this -- as "tree" with root at left Foo(Bar(get(X)), or with root at right (((Foo)Bar)get)X? Or maybe as a ...
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1answer
214 views

How does an optimizing compiler react to a program with nested loops?

Say you have a bunch of nested loops. public void testMethod() { for(int i = 0; i<1203; i++){ //some computation for(int k=2; k<123; k++){ ...
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2answers
161 views

How do I simplify a compiler/interpreter?

Recently I wrote an interpreter for operations on sparse matrices (a "sparse matrix calculator") in lex/yacc. The language is still very bare bones and doesn't even include control structures or ...
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13answers
1k views

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 ...
5
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1answer
293 views

Why do some embedded projects shun cross-compiling?

As I've been getting into embedded systems I've noticed that some projects (Arch Arm and OpenBSD for example) frown upon cross compiling. What is the reasoning for this? Is a cross-compiled binary ...
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2answers
190 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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4answers
734 views

How does assembly relate to machine/binary code

How does assembly relate to machine/binary code. For example here is how to print to the screen in mikeOS(a small pure assembly OS), mikeOS it uses NASM to assemble. BITS 16 ORG 32768 ...
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4answers
1k views

Computation Program Not Running at 100% CPU Utilization

I have a program which has a GUI and performs some very heavy mathematical computations for a couple of minutes and then outputs a result. When I try to directly interface it through its DLL's, it ...
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2answers
88 views

Storing tokens during lexing stage

I am currently implementing a lexer that breaks XML files up into tokens, I'm considering ways of passing the tokens onto a parser to create a more useful data structure out of said tokens - my ...
3
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2answers
500 views

Are (C) object files created with different compilers binary-compatible?

I understand that C++ compilers are not compatible with each other. However, I was unable to find anything on this topic for C in particular. I know that the C standard leaves a lot of room for ...
0
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1answer
629 views

Is the microsoft C compiler (cl.exe) a compiler driver or a compiler?

gccand clang are both known to be compiler drivers. As such, the gcc executable does not compile anything itself. Rather, it calls the compiler (cc1), assembler (as) and linker (ld) with the right ...
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7answers
2k views

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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5answers
329 views

How to alter the code at runtime in an interpreter?

While reading the difference between Compiler and interpreter , I found the following differences fromt he internet. Advantages of using compiler: Since compiler converts the program to native code ...
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1answer
182 views

LLVM case: is the success due to the algorithms? [closed]

I'm not sure if this is a subjective question, I hope not but I'm not proficient with LLVM so I'm just wondering: how come it's become so popular and so widespread used in the industry? Were the ...
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1answer
3k views

What would be the best way to learn about compilers, and executable formats? [duplicate]

I want to write my own compiler for my own language. Yes, it's going to be hard, and it will take long, but I think it will be worth it. I have looked into OSDev.org, and read about executable ...
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5answers
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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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3answers
224 views

Why can't we program without compiling (using an IDE/debugger)? [closed]

I find it very interesting that even people who design a particular framework still have to rely on compiling to ensure the code is correct. I don't mean for 100s of lines of code, but 2-10 lines. I ...
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12answers
1k views

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 ...
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3answers
196 views

Requiring a specific order of compilaiton

When designing a compiled programming language, is it a bad idea to require a specific order of compilation of separate units, according to their dependencies? To illustrate what I mean, consider C. ...
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2answers
1k views

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

I know this is abstract as it's all about signals and switch - (electronics) - underneath, but is there a easy way to visualize the step between assembling code to machine code. For example if you ...
12
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2answers
911 views

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 ...
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4answers
187 views

Does boostrapping limit the achievable speed of the new compiler?

I have a good grasp on how the C compiler was boostrapped from itself and how that must have been very efficient, since the first pre-bootstrapping version was written in assembler, which is as low ...
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4answers
647 views

Why don't compilers support non-English keywords? [closed]

When you read C, C#, Java, Python, PHP and many other programming languages all the syntax is written in English. Simple code like this if (X+1 > 4) { } while (A == true) { } Is written in ...
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3answers
457 views

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 is taken care ...
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4answers
1k views

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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10answers
4k views

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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3answers
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Writing a Compiler Compiler - Insight on Use and Features

This is part of a series of questions which focuses on the sister project to the Abstraction Project, which aims to abstract the concepts used in language design in the form of a framework. The ...
8
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4answers
556 views

Why aren't VM languages compiled just once?

(First of all, I should make clear that compilers and virtual machines (aka) are a completely unknown field for me) As I understand it, every time a Java/C#/... application is run, a VM is invoked ...
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1answer
275 views

How small is the footprint of a small C compiler?

This week I could optimize using a reduced C library that allowed a drastic shrinkage in code size - from about 60 K to about 6 K and then we could load the code in the 8 K on-chip memory of an FPGA ...
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3answers
221 views

What process do typical (the majority) of high level language compilers use when changing a source-code's variable name to a machine code name?

Do long (very long) variable names slow down the compilation of source code? I'm aware that the length of variables has 0% impact on interpretation as the compiler changes them to machine code which ...
6
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1answer
180 views

.NET BCL Change Analysis - Uses Beyond Sating Curiosity

This is part of a series of questions which focuses on the Abstraction Project, which aims to abstract the concepts used in language design in the form of a framework. There is a sister project to ...
3
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1answer
628 views

Does setting a function public affect the C# compiler's ability to inline the function as an optimization?

This could be either for the .NET or Mono compilers. I know that under certain conditions the compiler can inline functions (e.g. small, single call site, etc.) as an optimization. However, if the ...
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4answers
22k views

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 ...
1
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2answers
149 views

Will a binary include methods that are not called in the source code?

[Potentially misleading title, but I'm not sure how best to word it.] Theoretical question on compilers and language design. Say I'm re-implementing a method in a code base. Instead of removing or ...
8
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2answers
476 views

What is the current state of SECD and SKI machine use and research? [closed]

I'm doing some independent research/study with a professor who's a very functional guy. The goal is to examine more of what's happening behind the scenes with functional languages than we normally ...
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1answer
324 views

How to use BDD to unit test a compiler?

My team is writing a compiler for a domain-specific language (DSL) which will be integrated into an IDE. Right now, we are focused on the analysis phase of the compiler. We are not using any existing ...
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2answers
2k views

How would I make a compiler in C++? [closed]

This probably been asked for but I can't google "How to make a compiler in C++" because I will just get "How to compile C++" as the results. Anyway, for my question, I'd like to make a simple ...
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9answers
16k views

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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5answers
893 views

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 ...