How Can I Reliably Determine if My C Environment is 32-bit or 64-bit?

Distinguishing Between 32 and 64-bit Environments in C

Determining the bit width (32 vs 64) of a C compilation is crucial for certain operations. While a common approach employs macros to compare maximum values, it raises concerns about possible failures.

Suggested Method:

Instead of relying solely on macros, consider using a cross-platform approach that leverages compiler-specific definitions. Define custom variables (e.g., ENVIRONMENT64 and ENVIRONMENT32) and set them based on the compiler's platform. Here's a sample code snippet:

// Check Windows
#if _WIN32 || _WIN64
#if _WIN64
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif
#endif

// Check GCC
#if __GNUC__
#if __x86_64__ || __ppc64__
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif
#endif

// Check based on custom variables
#ifdef ENVIRONMENT64
DoMy64BitOperation();
#else
DoMy32BitOperation();
#endif

Alternative Solution:

Alternatively, you can set these variables explicitly from the compiler command line:

-DENVIRONMENT64=1

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