You’re the one running gcc (or g++). It’s a compiler, used by developers. End-user systems may not have any version of gcc. It’s glibc and libstdc++ you need to worry about. But in general, Linux does not aim for binary compatibility. Do not expect any binary executable to run properly on any other distribution/major version. … Read more
Here is a version of your code which doesn’t break aliasing rules: class Foo { public: Foo() : userData(0L) { } long userData; }; void Destroy(Foo* pFoo) { if (–pFoo->userData <= 0) { delete pFoo; } } int main() { int i = 0; while (i < 10) { Foo* pFoo = new Foo(); pFoo->userData … Read more
Once a binary is created from C++ source files, the original source files are not needed in order to run the program. You can distribute only the compiled program. solved How to compile C++ codes in Linux with source files hidden? [closed]
Because <array> got indirectly included from somewhere and you made the mistake of using namespace std, “array” in ErrorMessage refers to that name in the std namespace. That is a class template, not a type – hence the error message. Outside of value, its array is called value::array. (The typedef value::array array in value is … Read more
A large portion of this question will depend on what A, B and C really are (and the compiler will optimise it, as shown below). Simple types, definitely not worth worrying about. If they are some kind of “big number math” objects, or some complicated data type that needs 1000 instructions for each “is this … Read more
These *.d files usually (and just conventionally) are make dependencies (but perhaps, and unlikely, D-language source code). The GCC compiler knows about -M (and related) preprocessor option, which asks make to …. Instead of outputting the result of preprocessing, output a rule suitable for make describing the dependencies of the main source file. With the … Read more
att vs intel syntax has been covered many times, here and other places. Assembly language is a language defined by the assembler, the particular program used to convert the ASCII assembly language into machine code for the particular target you are interested in. Unlike say a C or C++ compiler where there is a standard … Read more
Well this will run until EOF is detected. EOF can be ‘inserted’ pressing ctrl+D in Linux terminal. It works OK then. change while ((c = getchar()) != EOF) to while ((c = getchar()) != ‘\n’) and it will only ask you for one line of input and then return the result. btw: main is of … Read more
Instruction size does not related to data or address bus size. Some 16-bit x86 CPUs have 3 totally different sizes with 8-bit data bus, 20-bit address bus and variable length instruction size. Modern 32-bit or 64-bit x86 have variable length instruction too for backward compatibility. Just look at the movl $0x542412e6, %eax and pushl 0x08048dd6 … Read more
You cannot have any strictly ANSI compatible event loop on Linux, because the purpose of an event loop is to multiplex cleverly several inputs; on Linux to do that multiplexing, you have to call some syscalls like poll(2), pselect(2) or friends, and all these syscalls are not standardized in ANSI C (or ISO C99, or … Read more
You should compile with g++, not gcc because it’s C compiler and <vector> is a C++ header file (not mentioning <vecotr> which is a typo) If you have to use C compiler, you have to remove all C++ dependencies from header files which are included from the C sources. solved Compile c/c++ program using gcc … Read more
It looks like you are trying to do something similar to this: #include <stdio.h> double hullSpeed(double lgth) { double result; __asm__( “fldl %1\n\t” //st(0)=>st(1), st(0)=lgth . FLDL means load double float “fsqrt\n\t” //st(0) = square root st(0) “fmulp\n\t” //Multiplies st(0) and st(1) (1.34). Result in st(0) : “=&t” (result) : “m” (lgth), “0” (1.34)); return … Read more
The printf function has the following declaration: int printf(const char *format, …); The first argument must be a pointer to a char array, but any additional arguments can be of any type, so it’s not a compiler error if a format specifier mismatches the parameter (although it is undefined behavior). This still works however because … Read more
Just download and install the free and prebuilt Codesourcery/Mentor Arm cross-compiler and toolchain from here. 2 solved How to compile the cross-compiler arm-linux-eabi-gcc? [closed]
First of all, C functions are call-by-value: the int x arg in the function is a copy. Modifying it doesn’t modify the caller’s copy of whatever they passed, so your swap makes zero sense. Second, you’re using the return value of the function, but you don’t have a return statement. In C (unlike C++), it’s … Read more