- 1 year ago
How to pack a struct tightly on Windows?
In C or C++, you can use compiler-specific pragmas or attributes to pack a struct tightly on Windows. Here's how you can achieve this using different compilers:
- Visual C++ (MSVC):
cpp#pragma pack(push, 1)
struct MyStruct {
// struct members
};
#pragma pack(pop)
- GCC (MinGW, Cygwin, etc.):
cppstruct __attribute__((packed)) MyStruct {
// struct members
};
- Clang (LLVM):
cppstruct __attribute__((packed)) MyStruct {
// struct members
};
By using the pragma pack
directive or the __attribute__((packed))
attribute, you can instruct the compiler to pack the struct tightly, without any padding between members.
Note that packing a struct tightly can have performance implications due to potential alignment issues. It's important to carefully consider the impact of packing on the performance and portability of your code.
Additionally, keep in mind that using compiler-specific pragmas or attributes may make your code less portable across different compilers and platforms. It's recommended to isolate such compiler-specific code using preprocessor directives, so that it's only applied when compiling with the specific compiler where it's necessary.