Add support for LLVM Flang

.github/workflows/dynamic_arch.yml

@@ -151,40 +151,53 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        msystem: [MINGW64, MINGW32, CLANG64]
+        msystem: [MINGW64, MINGW32, CLANG64, CLANG32]
         idx: [int32, int64]
         build-type: [Release]
         include:
           - msystem: MINGW64
             idx: int32
             target-prefix: mingw-w64-x86_64
-            fc-pkg: mingw-w64-x86_64-gcc-fortran
+            fc-pkg: fc
           - msystem: MINGW32
             idx: int32
             target-prefix: mingw-w64-i686
-            fc-pkg: mingw-w64-i686-gcc-fortran
+            fc-pkg: fc
           - msystem: CLANG64
             idx: int32
             target-prefix: mingw-w64-clang-x86_64
+            fc-pkg: fc
+            # Compiling with Flang 16 seems to cause test errors on machines
+            # with AVX512 instructions. Revisit after MSYS2 distributes Flang 17.
+            no-avx512-flags: -DNO_AVX512=1
+          - msystem: CLANG32
+            idx: int32
+            target-prefix: mingw-w64-clang-i686
+            fc-pkg: cc
             c-lapack-flags: -DC_LAPACK=ON
           - msystem: MINGW64
             idx: int64
             idx64-flags: -DBINARY=64 -DINTERFACE64=1
             target-prefix: mingw-w64-x86_64
-            fc-pkg: mingw-w64-x86_64-gcc-fortran
+            fc-pkg: fc
           - msystem: CLANG64
             idx: int64
             idx64-flags: -DBINARY=64 -DINTERFACE64=1
             target-prefix: mingw-w64-clang-x86_64
-            c-lapack-flags: -DC_LAPACK=ON
+            fc-pkg: fc
+            # Compiling with Flang 16 seems to cause test errors on machines
+            # with AVX512 instructions. Revisit after MSYS2 distributes Flang 17.
+            no-avx512-flags: -DNO_AVX512=1
           - msystem: MINGW64
             idx: int32
             target-prefix: mingw-w64-x86_64
-            fc-pkg: mingw-w64-x86_64-gcc-fortran
+            fc-pkg: fc
             build-type: None
         exclude:
           - msystem: MINGW32
             idx: int64
+          - msystem: CLANG32
+            idx: int64
 
     defaults:
       run:
@@ -209,7 +222,7 @@ jobs:
           install: >-
             base-devel
             ${{ matrix.target-prefix }}-cc
-            ${{ matrix.fc-pkg }}
+            ${{ matrix.target-prefix }}-${{ matrix.fc-pkg }}
             ${{ matrix.target-prefix }}-cmake
             ${{ matrix.target-prefix }}-ninja
             ${{ matrix.target-prefix }}-ccache
@@ -261,6 +274,7 @@ jobs:
                 -DTARGET=CORE2 \
                 ${{ matrix.idx64-flags }} \
                 ${{ matrix.c-lapack-flags }} \
+                ${{ matrix.no-avx512-flags }} \
                 -DCMAKE_C_COMPILER_LAUNCHER=ccache \
                 -DCMAKE_Fortran_COMPILER_LAUNCHER=ccache \
                 ..
@@ -280,9 +294,22 @@ jobs:
           key: ${{ steps.ccache-prepare.outputs.key }}
 
       - name: Run tests
+        id: run-ctest
         timeout-minutes: 60
         run: cd build && ctest
 
+      - name: Re-run tests
+        if: always() && (steps.run-ctest.outcome == 'failure')
+        timeout-minutes: 60
+        run: |
+          cd build
+          echo "::group::Re-run ctest"
+          ctest --rerun-failed --output-on-failure || true
+          echo "::endgroup::"
+          echo "::group::Log from these tests"
+          [ ! -f Testing/Temporary/LastTest.log ] || cat Testing/Temporary/LastTest.log
+          echo "::endgroup::"
+
 
   cross_build:
     runs-on: ubuntu-22.04

cmake/fc.cmake

@@ -3,7 +3,8 @@
 ## Description: Ported from portion of OpenBLAS/Makefile.system
 ##              Sets Fortran related variables.
 
-if (${F_COMPILER} STREQUAL "FLANG")
+if (${F_COMPILER} STREQUAL "FLANG" AND NOT CMAKE_Fortran_COMPILER_ID STREQUAL "LLVMFlang")
+  # This is for classic Flang. LLVM Flang is handled with gfortran below.
   set(CCOMMON_OPT "${CCOMMON_OPT} -DF_INTERFACE_FLANG")
   if (BINARY64 AND INTERFACE64)
     set(FCOMMON_OPT "${FCOMMON_OPT} -i8")
@@ -38,15 +39,17 @@ if (${F_COMPILER} STREQUAL "G95")
   endif ()
 endif ()
 
-if (${F_COMPILER} STREQUAL "GFORTRAN" OR ${F_COMPILER} STREQUAL "F95")
+if (${F_COMPILER} STREQUAL "GFORTRAN" OR ${F_COMPILER} STREQUAL "F95" OR CMAKE_Fortran_COMPILER_ID STREQUAL "LLVMFlang")
   set(CCOMMON_OPT "${CCOMMON_OPT} -DF_INTERFACE_GFORT")
-  # ensure reentrancy of lapack codes
-  set(FCOMMON_OPT "${FCOMMON_OPT} -Wall -frecursive")
-  # work around ABI violation in passing string arguments from C
-  set(FCOMMON_OPT "${FCOMMON_OPT} -fno-optimize-sibling-calls")
-  #Don't include -lgfortran, when NO_LAPACK=1 or lsbcc
-  if (NOT NO_LAPACK)
-    set(EXTRALIB "${EXTRALIB} -lgfortran")
+  if (NOT CMAKE_Fortran_COMPILER_ID STREQUAL "LLVMFlang")
+    # ensure reentrancy of lapack codes
+    set(FCOMMON_OPT "${FCOMMON_OPT} -Wall -frecursive")
+    # work around ABI violation in passing string arguments from C
+    set(FCOMMON_OPT "${FCOMMON_OPT} -fno-optimize-sibling-calls")
+    if (NOT NO_LAPACK)
+      # Don't include -lgfortran, when NO_LAPACK=1 or lsbcc
+      set(EXTRALIB "${EXTRALIB} -lgfortran")
+    endif ()
   endif ()
   if (NO_BINARY_MODE)
     if (MIPS64)