Questions tagged [gcc]
GCC is the GNU Compiler Collection. It's the de facto standard compiler for C, C++, Go, Fortran, and Ada on Linux and supports many other languages and platforms as well.
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
I am doing some numerical optimization on a scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a, but the call pow(a,6) is not optimized and ...
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fatal error: Python.h: No such file or directory
I am trying to build a shared library using a C extension file but first I have to generate the output file using the command below:
gcc -Wall utilsmodule.c -o Utilc
After executing the command, I ...
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Compiling an application for use in highly radioactive environments
We are compiling an embedded C++ application that is deployed in a shielded device in an environment bombarded with ionizing radiation. We are using GCC and cross-compiling for ARM. When deployed, our ...
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What is the difference between g++ and gcc?
What is the difference between g++ and gcc? Which one of them should be used for general c++ development?
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Why does the C preprocessor interpret the word "linux" as the constant "1"?
Why does the C preprocessor in GCC interpret the word linux (small letters) as the constant 1?
test.c:
#include <stdio.h>
int main(void)
{
int linux = 5;
return 0;
}
Result of $...
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Why is my program slow when looping over exactly 8192 elements?
Here is the extract from the program in question. The matrix img[][] has the size SIZE×SIZE, and is initialized at:
img[j][i] = 2 * j + i
Then, you make a matrix res[][], and each field in here is ...
anon
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How to automatically generate a stacktrace when my program crashes
I am working on Linux with the GCC compiler. When my C++ program crashes I would like it to automatically generate a stacktrace.
My program is being run by many different users and it also runs on ...
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How do I list the symbols in a .so file
How do I list the symbols being exported from a .so file? If possible, I'd also like to know their source (e.g. if they are pulled in from a static library).
I'm using gcc 4.0.2, if that makes a ...
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Why does the order in which libraries are linked sometimes cause errors in GCC?
Why does the order in which libraries are linked sometimes cause errors in GCC?
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GCC -fPIC option
I have read about GCC's Options for Code Generation Conventions, but could not understand what "Generate position-independent code (PIC)" does. Please give an example to explain me what does it mean.
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Debug vs Release in CMake
In a GCC compiled project,
How do I run CMake for each target type (debug/release)?
How do I specify debug and release C/C++ flags using CMake?
How do I express that the main executable will be ...
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What exactly is LLVM?
I keep hearing about LLVM all the time. It's in Perl, then it's in Haskell, then someone uses it in some other language? What is it?
What exactly distinguishes it from GCC (perspectives = safety etc.)...
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Undefined reference to vtable
When building my C++ program, I'm getting the error message
undefined reference to 'vtable...
What is the cause of this problem? How do I fix it?
It so happens that I'm getting the error for the ...
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How do you get assembler output from C/C++ source in GCC?
How does one do this?
If I want to analyze how something is getting compiled, how would I get the emitted assembly code?
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