arm64 compiler fixes

Author: perazz

.github/workflows/CI.yml

@@ -33,6 +33,8 @@ jobs:
         exclude:
           - os: macos-14  # No Intel on MacOS anymore since 2024
             toolchain: {compiler: intel, version: '2025.1'}
+          - os: macos-14  # Intel compiler does not support ARM (macos-14)
+            toolchain: {compiler: intel, version: '2025.2'}
           - os: macos-14  # gcc@10 not available on macos-14 (ARM64)
             toolchain: {compiler: gcc, version: 10}
           - os: windows-latest  # Doesn't pass build and tests yet

ci/test_features.sh

@@ -207,11 +207,8 @@ grep -q "✓ FAST: fast optimization flags found" output.txt || { echo "ERROR: F
 grep -q "✓ All compiler flag checks PASSED" output.txt || { echo "ERROR: Expected all checks to pass"; exit 1; }
 # Check compiler-specific flags (will depend on detected compiler)
 if grep -q "Detected compiler: gfortran" output.txt; then
-    # Check for either -march=native or -mcpu (Apple Silicon uses -mcpu)
-    if ! (grep -q "✓ Release: -march=native found" output.txt || grep -q "✓ Release: -mcpu found" output.txt); then
-        echo "ERROR: gfortran release architecture flag (-march=native or -mcpu) not found"
-        exit 1
-    fi
+    # Check for -mtune flag (portable tuning flag)
+    grep -q "✓ Release: -mtune found" output.txt || { echo "ERROR: gfortran release flag -mtune not found"; exit 1; }
     grep -q "✓ Fast: -ffast-math found" output.txt || { echo "ERROR: gfortran fast flag -ffast-math not found"; exit 1; }
 fi
 echo "✓ Production profile works"

example_packages/features_demo/fpm.toml

@@ -19,7 +19,7 @@ release.preprocess.cpp.macros = "RELEASE"
 
 # Compiler-specific features
 debug.gfortran.flags = "-Wall -fcheck=bounds"
-release.gfortran.flags = "-march=native"
+release.gfortran.flags = "-mtune=generic -funroll-loops"
 
 # Platform-specific features
 linux.preprocess.cpp.macros = "LINUX_BUILD"

example_packages/features_per_compiler/app/main.f90

@@ -126,17 +126,8 @@ function check_gfortran_flags(options, debug_on, release_on, fast_on, strict_on)
     end if
 
     if (release_on) then
-      ! Check for either -march or -mcpu (Apple Silicon uses -mcpu; -match=native may be re-resolved by gcc)
-      if (.not. (index(options, '-march') > 0 .or. index(options, '-mcpu') > 0)) then
-        print '(a)', '  ✗ Release: neither -march=native nor -mcpu found'
-        failed_count = failed_count + 1
-      else
-        if (index(options, '-march=native') > 0) then
-          print '(a)', '  ✓ Release: -march found'
-        else
-          print '(a)', '  ✓ Release: -mcpu found'
-        end if
-      end if
+      ! Check for -mtune flag (portable tuning flag that works on all platforms)
+      if (.not. check_flag(options, '-mtune', 'Release', '-mtune')) failed_count = failed_count + 1
       if (.not. check_flag(options, '-funroll-loops', 'Release', '-funroll-loops')) failed_count = failed_count + 1
     end if
 

example_packages/features_per_compiler/fpm.toml

@@ -34,7 +34,7 @@ debug.preprocess.cpp.macros = "DEBUG"
 
 # Release feature with base optimization, then per-compiler extensions
 release.flags = "-O3"  # Base optimization for ALL compilers (applied first)
-release.gfortran.flags = "-march=native -funroll-loops"
+release.gfortran.flags = "-mtune=generic -funroll-loops"
 release.ifort.flags = "-unroll"     # Unix/Linux/macOS Intel
 release.ifx.flags = "-unroll"       # Intel oneAPI
 

example_packages/features_with_dependency/fpm.toml

@@ -30,7 +30,7 @@ linux_specific.preprocess.cpp.macros = ["WITH_DEMO","LINUX_FEATURES"]
 
 # Feature combining compiler and dependency features
 gfortran_optimized.gfortran.dependencies.features_demo = { path = "../features_demo", features = ["release", "gfortran"] }
-gfortran_optimized.gfortran.flags = "-O3 -march=native"
+gfortran_optimized.gfortran.flags = "-O3 -mtune=generic -funroll-loops"
 gfortran_optimized.preprocess.cpp.macros = ["WITH_DEMO"]
 
 

test/fpm_test/test_features.f90

@@ -365,7 +365,7 @@ subroutine test_feature_collection_complex(error)
             & 'debug.linux.flags = "-DLINUX"', &
             & 'debug.windows.ifort.flags = "/DEBUG:FULL"', &
             & 'release.flags = "-O3"', &
-            & 'release.gfortran.flags = "-march=native"'
+            & 'release.gfortran.flags = "-mtune=generic -funroll-loops"'
         close(unit)
 
         call get_package_data(package, temp_file, error)
@@ -1501,7 +1501,7 @@ subroutine test_feature_compiler_flags_integration(error)
         write(unit, '(a)') '[features]'
         write(unit, '(a)') 'debug.gfortran.flags = "-g -Wall -fcheck=bounds"'
         write(unit, '(a)') 'debug.flags = "-g"'
-        write(unit, '(a)') 'release.gfortran.flags = "-O3 -march=native"'
+        write(unit, '(a)') 'release.gfortran.flags = "-O3 -mtune=generic -funroll-loops"'
         write(unit, '(a)') 'release.flags = "-O2"'
         write(unit, '(a)') ''
         write(unit, '(a)') '[profiles]'
@@ -1575,8 +1575,13 @@ subroutine test_feature_compiler_flags_integration(error)
             return
         end if
 
-        if (index(model%fortran_compile_flags, "-march=native") == 0) then
-            call test_failed(error, "Expected release gfortran flags to contain '-march=native'")
+        if (index(model%fortran_compile_flags, "-mtune") == 0) then
+            call test_failed(error, "Expected release gfortran flags to contain '-mtune'")
+            return
+        end if
+
+        if (index(model%fortran_compile_flags, "-funroll-loops") == 0) then
+            call test_failed(error, "Expected release gfortran flags to contain '-funroll-loops'")
             return
         end if
 

test/fpm_test/test_manifest.f90

@@ -1762,7 +1762,7 @@ subroutine test_features_demo_serialization(error)
             & '', &
             & '# Compiler-specific features', &
             & 'debug.gfortran.flags = "-Wall -fcheck=bounds"', &
-            & 'release.gfortran.flags = "-march=native"', &
+            & 'release.gfortran.flags = "-mtune=generic -funroll-loops"', &
             & '', &
             & '# Platform-specific features', &
             & 'linux.preprocess.cpp.macros = "LINUX_BUILD"', &