Support legacy Intel macOS loaders

.github/workflows/release.yml

@@ -72,6 +72,7 @@ jobs:
           OPENSSL_VERSION: 3.5.7
           OPENSSL_TARGET: ${{ matrix.openssl_target }}
           CROSS_PREFIX: ${{ matrix.cross_prefix }}
+          MACOSX_DEPLOYMENT_TARGET: ${{ matrix.target == 'macos-amd64' && '10.5' || '' }}
         run: |
           curl --fail --location --retry 3 \
             "https://www.openssl.org/source/openssl-${OPENSSL_VERSION}.tar.gz" \
@@ -105,6 +106,8 @@ jobs:
 
       - name: Build macOS executable with static OpenSSL
         if: startsWith(matrix.target, 'macos-')
+        env:
+          MACOSX_DEPLOYMENT_TARGET: ${{ matrix.target == 'macos-amd64' && '10.5' || '' }}
         run: |
           OPENSSL_LIBDIR="$(find "$GITHUB_WORKSPACE/openssl-static" -type f -name libssl.a -exec dirname {} \;)"
           make "${{ matrix.target }}" \

Makefile

@@ -102,6 +102,7 @@ else
 endif
 CC_MACOS_ARM64 ?= $(CC)
 CC_MACOS_AMD64 ?= $(CC)
+MACOS_AMD64_MIN ?= 10.5
 ifeq ($(HOST_ARCHNAME),ppc32be)
 	CC_PPC32BE ?= $(CC)
 else
@@ -153,7 +154,7 @@ $(DIST)/fossmark-macos-arm64: $(DRIVER) $(ASM_ARM64) | $(DIST)
 	@echo "built $@"
 
 $(DIST)/fossmark-macos-amd64: $(DRIVER) $(ASM_AMD64) | $(DIST)
-	$(CC_MACOS_AMD64) -arch x86_64 $(CFLAGS) $(TLS_CFLAGS) $(PTHREAD) $(LDFLAGS) -o $@ $(DRIVER) $(ASM_AMD64) $(LDLIBS)
+	MACOSX_DEPLOYMENT_TARGET=$(MACOS_AMD64_MIN) $(CC_MACOS_AMD64) -arch x86_64 -mmacosx-version-min=$(MACOS_AMD64_MIN) $(CFLAGS) $(TLS_CFLAGS) $(PTHREAD) $(LDFLAGS) -Wl,-no_fixup_chains -o $@ $(DRIVER) $(ASM_AMD64) $(LDLIBS)
 	@echo "built $@"
 
 # When the host is Linux/ARM64 or Linux/AMD64, the native binary IS one of the

README.md

@@ -71,6 +71,11 @@ Apple Clang can build either macOS architecture with `-arch`. Windows timing
 and allocation code exists in the driver, but the Makefile does not include a
 Windows target and the x86-64 assembly currently follows the System V ABI.
 
+The macOS AMD64 target is linked for macOS 10.5 and disables chained fixups so
+its Mach-O load commands are understood by legacy Intel Macs. Override the
+deployment floor when needed with `MACOS_AMD64_MIN`, for example
+`make macos-amd64 MACOS_AMD64_MIN=10.8`.
+
 Run the benchmark with extra per-test details by passing `--verbose`:
 
 ```sh

src/main.c

@@ -35,13 +35,14 @@
 #if defined(__APPLE__)
 #  include <sys/types.h>
 #  include <sys/sysctl.h>
+#  include <mach/mach_time.h>
 #endif
 
 /* Change this at build time with -DFM_API_BASE_URL=\"https://host\". */
 #ifndef FM_API_BASE_URL
 #  define FM_API_BASE_URL "https://fossbench.net"
 #endif
-#define FM_VERSION "0.1.3-hotfix1"
+#define FM_VERSION "0.1.3-hotfix2"
 
 /* ---------- platform identification (for the banner only) ---------- */
 
@@ -94,6 +95,18 @@ static double now_seconds(void)
 	QueryPerformanceCounter(&t);
 	return (double)t.QuadPart / (double)f.QuadPart;
 }
+#elif defined(__APPLE__)
+static double now_seconds(void)
+{
+	static mach_timebase_info_data_t timebase;
+	uint64_t ticks;
+
+	if (timebase.denom == 0)
+		mach_timebase_info(&timebase);
+	ticks = mach_absolute_time();
+	return (double)ticks * (double)timebase.numer /
+	       (double)timebase.denom * 1e-9;
+}
 #else
 #  include <time.h>
 static double now_seconds(void)