Implement cross-platform endian.h compatibility solution

Replace broken __GNUC__ undefining approach with elegant local endian.h:

- Create local ext/fastpbkdf2/endian.h that handles all platforms
- macOS: Use machine/endian.h and libkern/OSByteOrder.h
- Windows: Hardcode little-endian constants for x86/x64
- Linux: Use system endian.h via include_next
- Simplify wrapper to just include fastpbkdf2.c cleanly
- Update coverage job to run even if some test matrix jobs fail

This avoids breaking Windows MinGW toolchain headers while preserving pristine vendor files and maintaining cross-platform compatibility.

Author: voltechs

.github/workflows/ci.yml

@@ -74,6 +74,7 @@ jobs:
   coverage:
     runs-on: ubuntu-latest
     needs: test
+    if: always() # Run even if some test jobs fail
 
     steps:
       - uses: actions/checkout@v4
@@ -83,6 +84,7 @@ jobs:
         with:
           name: coverage-report
           path: coverage/
+        continue-on-error: true # In case no coverage artifact was uploaded
 
       - name: Upload coverage to Qlty
         uses: qltysh/qlty-action/coverage@v1

README.md

@@ -41,7 +41,6 @@ Real-world benchmarks on macOS (x86_64) show consistent performance improvements
 
 ### Low Security (1,000 iterations)
 
-
 | Algorithm | FastPBKDF2 | OpenSSL | Speedup   | Use Case                 |
 | --------- | ---------- | ------- | --------- | ------------------------ |
 | SHA1      | 0.12ms     | 0.21ms  | **1.75x** | Basic web authentication |
@@ -173,7 +172,6 @@ The gem compiles the fastpbkdf2 C library during installation, so no external de
 
 This gem is designed to compile and run across major platforms:
 
-
 ### ✅ Supported Platforms
 
 - **macOS**: Intel (x86_64) and Apple Silicon (arm64)
@@ -188,11 +186,9 @@ This gem is designed to compile and run across major platforms:
 - **SIMD Optimizations**: The underlying fastpbkdf2 C library includes architecture-specific optimizations
 - **Compiler Detection**: Automatically adapts compilation flags for GCC, Clang, and MSVC
 
-
 ### Build Requirements by Platform
 
 #### macOS
-
 ```bash
 
 # Xcode Command Line Tools (includes clang and OpenSSL)

ext/fastpbkdf2/endian.h

@@ -0,0 +1,71 @@
+/*
+ * endian.h - Cross-platform endian compatibility header
+ * 
+ * This file provides endian.h compatibility for platforms that don't have it
+ * (like Windows and macOS). It gets included by fastpbkdf2.c when __GNUC__ is defined.
+ */
+
+#ifndef FASTPBKDF2_ENDIAN_H
+#define FASTPBKDF2_ENDIAN_H
+
+#ifdef __APPLE__
+  /* macOS approach: use system headers to define endian macros */ 
+  #include <machine/endian.h>
+  #include <libkern/OSByteOrder.h>
+  
+  /* Define the Linux-style endian macros that fastpbkdf2.c expects */
+  #ifndef __BYTE_ORDER
+    #define __BYTE_ORDER    BYTE_ORDER
+  #endif
+  #ifndef __LITTLE_ENDIAN
+    #define __LITTLE_ENDIAN LITTLE_ENDIAN
+  #endif
+  #ifndef __BIG_ENDIAN
+    #define __BIG_ENDIAN    BIG_ENDIAN
+  #endif
+
+#elif defined(_WIN32)
+  /* Windows doesn't have endian.h, but it's always little-endian on x86/x64 */
+  #ifndef __BYTE_ORDER
+    #define __BYTE_ORDER    1234
+  #endif
+  #ifndef __LITTLE_ENDIAN
+    #define __LITTLE_ENDIAN 1234
+  #endif
+  #ifndef __BIG_ENDIAN
+    #define __BIG_ENDIAN    4321
+  #endif
+
+#else
+  /* Linux and other Unix systems - include the real system endian.h */
+  #if __has_include(<endian.h>)
+    #include_next <endian.h>
+  #elif __has_include(<sys/endian.h>)
+    #include <sys/endian.h>
+  #else
+    /* Fallback definitions for systems without endian headers */
+    #ifndef __BYTE_ORDER
+      #ifdef __BYTE_ORDER__
+        #define __BYTE_ORDER __BYTE_ORDER__
+      #else
+        #define __BYTE_ORDER 1234  /* Assume little-endian */
+      #endif
+    #endif
+    #ifndef __LITTLE_ENDIAN
+      #ifdef __ORDER_LITTLE_ENDIAN__
+        #define __LITTLE_ENDIAN __ORDER_LITTLE_ENDIAN__
+      #else
+        #define __LITTLE_ENDIAN 1234
+      #endif
+    #endif
+    #ifndef __BIG_ENDIAN
+      #ifdef __ORDER_BIG_ENDIAN__
+        #define __BIG_ENDIAN __ORDER_BIG_ENDIAN__
+      #else
+        #define __BIG_ENDIAN 4321
+      #endif
+    #endif
+  #endif
+#endif
+
+#endif /* FASTPBKDF2_ENDIAN_H */

ext/fastpbkdf2/fastpbkdf2_wrapper.c

@@ -5,37 +5,12 @@
  * without modifying the upstream source files.
  */
 
-/* Set up platform-specific environment before including fastpbkdf2.c */
-#ifdef __APPLE__
-  /* On macOS, we need to provide the endian.h functionality */
-  #include <machine/endian.h>
-  #include <libkern/OSByteOrder.h>
-  
-  /* Define the Linux-style endian macros that fastpbkdf2.c expects */
-  #ifndef __BYTE_ORDER
-    #define __BYTE_ORDER    BYTE_ORDER
-  #endif
-  #ifndef __LITTLE_ENDIAN
-    #define __LITTLE_ENDIAN LITTLE_ENDIAN
-  #endif
-  #ifndef __BIG_ENDIAN
-    #define __BIG_ENDIAN    BIG_ENDIAN
-  #endif
-  
-  /* Redefine __GNUC__ temporarily to prevent endian.h include in fastpbkdf2.c */
-  #ifdef __GNUC__
-    #define __FASTPBKDF2_SAVED_GNUC__ __GNUC__
-    #undef __GNUC__
-  #endif
-#endif
+/* 
+ * fastpbkdf2_wrapper.c - Cross-platform wrapper for fastpbkdf2.c
+ * 
+ * This wrapper includes fastpbkdf2.c with cross-platform endian compatibility.
+ * The local endian.h file handles platform differences automatically.
+ */
 
 /* Now include the actual fastpbkdf2.c implementation */
 #include "../../vendor/fastpbkdf2/fastpbkdf2.c"
-
-#ifdef __APPLE__
-  /* Restore __GNUC__ if it was defined */
-  #ifdef __FASTPBKDF2_SAVED_GNUC__
-    #define __GNUC__ __FASTPBKDF2_SAVED_GNUC__
-    #undef __FASTPBKDF2_SAVED_GNUC__
-  #endif
-#endif

ext/fastpbkdf2/fastpbkdf2_wrapper.h

@@ -8,7 +8,7 @@
 #ifndef FASTPBKDF2_WRAPPER_H
 #define FASTPBKDF2_WRAPPER_H
 
-/* macOS/Apple platform compatibility fixes */
+/* Platform-specific compatibility fixes */
 #ifdef __APPLE__
   /* On macOS, we have __GNUC__ but don't want to use the GCC-specific 
    * endian.h and __BYTE_ORDER checks. Let's define the endian macros
@@ -28,6 +28,20 @@
   #endif
 #endif
 
+/* Windows platform compatibility fixes */
+#ifdef _WIN32
+  /* Windows doesn't have endian.h, but it's always little-endian on x86/x64 */
+  #ifndef __BYTE_ORDER
+    #define __BYTE_ORDER    1234
+  #endif
+  #ifndef __LITTLE_ENDIAN
+    #define __LITTLE_ENDIAN 1234
+  #endif
+  #ifndef __BIG_ENDIAN
+    #define __BIG_ENDIAN    4321
+  #endif
+#endif
+
 /* Include the actual fastpbkdf2 header */
 #include "../../vendor/fastpbkdf2/fastpbkdf2.h"