All Questions
Tagged with compiler-construction c
839 questions
0
votes
1
answer
75
views
Use flex to parse ":" and ".:" in expressions
I have a lex file, and based on the original, I would like to add support for recognizing (.:). My modifications are as follows:
%option caseless
ALP [a-z]+
NUM [0-9]+
REF {ALP}{NUM}
...
- 35
0
votes
1
answer
87
views
How can I elegantly put a big constant matrix without it being basically unreadable?
I'm writing a compiler project for school and I need to put a table of precalculated values into my code. The problem is that it is unreadable. How should I approach this problem?
So far I'm doing it ...
2
votes
2
answers
114
views
Translation limits of an identifier in C
I have started to write my own C compiler for the purpose of education. My goal is to be mostly C99 standard conform. Now I have a question about the maximum length of an identifier.
This is an ...
2
votes
1
answer
113
views
What is the exact compiler optimization applied here expect for tail recursion elimination?
I'm compiling a simple C program, implementing an inorder tree traversal function:
void inorderTraversal(struct TreeNode* root) {
if (root == NULL) {
return;
}
inorderTraversal(...
- 23
61
votes
5
answers
7k
views
Can you find a real example of "time travel" caused by undefined behaviour?
I am curious. Does anyone know a non-hypothetical C or C++ counterexample to the myth that "the impact of the undefined behaviour is limited to code which runs after the line with undefined ...
- 1,765
0
votes
1
answer
63
views
Invalid initializer error with anonymous structs
I have this code here:
Void() aba ()
{
}
#define std_Dynamic_Array(T) struct{Int32() count; Int32() capacity; T* memory; }
Void() no_body_func (Int32() b);
Int32() test_func (Int32()*** a)
{
}
Int32() ...
- 501
0
votes
3
answers
144
views
When inlining a C function, can an optimizing compiler dereference a pointer more times than explicitly written in the source code?
Consider the following code:
int y = 1;
int* p = &y;
inline int f(int x) {
return x + x;
}
int g(void) {
return f(*p);
}
In this code, there is one explicit dereference.
Is a C compiler ...
-1
votes
1
answer
60
views
flex and bison behave unexpectedly towards my input
I was trying to write a logical expression evaluation tool with flex and bison. I've gone over the code many times but when I run the executable it just ignores my input and prints Syntax error after ...
- 25
1
vote
1
answer
134
views
What is the reasoning behind this boilerplate start-up code?
Here's a snippet from disassembled output of a simple program with gcc on Linux:
400478: ff 15 6a 0b 20 00 callq *0x200b6a(%rip) # 600fe8 <__libc_start_main@GLIBC_2.2.5>
...
- 1,269
1
vote
0
answers
58
views
Unknown type name ‘Node’ in the parser file. (Yacc program)
I've been working on a Yacc program (parser.y) to develop a small compiler that handles arithmetic operations. I'm using Yacc (Bison) and Lex tools to generate the parser and lexical analyzer, ...
- 41
-3
votes
1
answer
190
views
What is the proper way to retrieve error handling from a compiler to an ide? [closed]
I have written my own programming language and have finished the self hosting compiler for it. I am now writing the ide frontend in windows for this compiler backend.
The issue is I created all the ...
- 30
-3
votes
3
answers
129
views
How does does compiler know the definition of pre defined function even before linker haven't linked object file and library file?
We know that definition of pre defined functions are in library files, and it is the job of linker to link that library code(which is already compiled) to our object file (which has been created after ...
2
votes
0
answers
77
views
Load function written in amd64 assembly into memory and call it
I am trying to write a small jit compiler. For that, I need to somehow load new code into memory and then execute it.
Given the output of the compiler for a function that simply adds the 2nd and 3rd ...
- 396
2
votes
0
answers
137
views
Write a gcc plugin that inserts macros at the beginning of each function
I understand that I can use __cyg_profile_func_enter and -finstrument-functions to insert code, but is it possible to insert macros by writing a gcc plugin?
Is there any documentation or possibly an ...
- 39
3
votes
1
answer
519
views
Can I use a different C standard library without re-compiling the compiler?
I just read this about C standard library:
When compiling C code, the C standard library cannot be switched per-compilation. It is necessary to build the entire compiler toolchain for the selected C ...
- 235