260128.164142.CST [skip ci] drop support for Classic Flang

Author: zaikunzhang

.github/workflows/cmake.yml

@@ -67,7 +67,7 @@ jobs:
           - os: ubuntu-latest
             toolchain: {compiler: intel, version: '2024.1', cflags: '-Wall -Werror', fflags: '-warn all -debug extended -fimplicit-none -standard-semantics'}
 
-          # What follows contains the toolchains for Windows, including gcc, intel classic, and intel.
+          # What follows contains the toolchains for Windows, including gcc, intel-classic, and intel.
           - os: windows-latest
             toolchain: {compiler: gcc, version: 11, cflags: '-Wall -Wextra -Wpedantic -Werror', fflags: '-Wall -Wextra -Wpedantic -Werror -fimplicit-none -fcheck=all -fstack-check -Wno-function-elimination'}
           - os: windows-latest
@@ -184,7 +184,7 @@ jobs:
       fail-fast: false
       matrix:
         toolchain:
-          # Classic Flang family with -Mchkptr would fail. See https://forums.developer.nvidia.com/t/bug-in-nvfortran-with-mchkptr-for-unallocated-optional-arguments/223220
+          # Flang family with -Mchkptr may fail. See https://forums.developer.nvidia.com/t/bug-in-nvfortran-with-mchkptr-for-unallocated-optional-arguments/223220
           # As of 20240220, aflang with -Mbounds would fail due to the bug at https://github.com/flang-compiler/flang/issues/1238
           - {compiler: nvfortran, cflags: '-Wall -Wextra -Wpedantic -Werror', fflags: '-C -Wall -Wextra -Minform=warn -Mstandard -Mbounds -Mchkstk'}
           - {compiler: flang, cflags: '-Wall -Wextra -Wpedantic -Werror', fflags: '-std=f2018 -pedantic -fimplicit-none -Werror'}

.github/workflows/cmake_pi.yml

@@ -82,8 +82,8 @@ jobs:
           cmake --build . --target install
           cmake --build . --target tests
 
-          # As of 20240316, CMake test fails on cobyla with the Classic flang, AOCC flang, and
-          # nvfortran. See https://github.com/libprima/prima/issues/165
+          # As of 20240316, CMake test fails on cobyla with the AOCC flang and nvfortran.
+          # See https://github.com/libprima/prima/issues/165
           if [[ $FC == 'gfortran' ]] ; then
               ctest --output-on-failure -V -E "stress"
           else

CMakeLists.txt

@@ -32,7 +32,7 @@ if (PRIMA_HEAP_ARRAYS)
     endif ()
   elseif (CMAKE_Fortran_COMPILER_ID MATCHES "NAG")  # nagfor
     set (CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -recursive")  # What about stack/heap?
-  elseif (CMAKE_Fortran_COMPILER_ID MATCHES "LLVMFlang")  # flang-new
+  elseif (CMAKE_Fortran_COMPILER_ID MATCHES "LLVMFlang")  # LLVM Flang
     # See https://github.com/llvm/llvm-project/issues/88344
     set (CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -fno-stack-arrays -mmlir -fdynamic-heap-array")
   elseif (CMAKE_Fortran_COMPILER_ID MATCHES "Flang")  # Classic Flang and AOCC Flang

fortran/common/linalg.f90

@@ -39,7 +39,7 @@ module linalg_mod
 !
 ! Started: July 2020
 !
-! Last Modified: Thu 14 Aug 2025 07:36:47 AM CST
+! Last Modified: Wed 28 Jan 2026 04:15:53 PM CST
 !--------------------------------------------------------------------------------------------------!
 
 implicit none
@@ -654,10 +654,9 @@ function solve(A, b) result(x)
     return
 end if
 
-! Zaikun 20220527: With the following code, the classic flang 17.0, Huawei Bisheng flang 1.3.3,
-! NVIDIA nvfortran 24.1, and AOCC 4.2 flang, and Arm Fortran Compiler version 23.1 raise a false
-! positive error of out-bound subscripts when invoked with the -Mbounds flag.
-! See https://github.com/flang-compiler/flang/issues/1238
+! Zaikun 20220527: With the following code, Huawei Bisheng flang 2.1.0, Arm Fortran Compiler 23.1,
+! and AOCC 5.1 flang, which raise a false positive error about out-bound subscripts when invoked
+! with the -Mbounds flag. See https://github.com/flang-compiler/flang/issues/1238
 if (istril(A)) then
     do i = 1, n
         x(i) = (b(i) - inprod(A(i, 1:i - 1), x(1:i - 1))) / A(i, i) ! INPROD = 0 if I == 1.
@@ -2223,6 +2222,7 @@ function trueloc(x) result(loc)
 
 ! Postconditions
 if (DEBUGGING) then
+    write(*, *) 'DEBUG: In TRUELOC, LOC = ', loc, ', X = ', x, ', N = ', size(x), linspace(1_IK, n, n)
     call assert(all(loc >= 1 .and. loc <= n), '1 <= LOC <= N', srname)
     call assert(size(loc) == count(x), 'SIZE(LOC) == COUNT(X)', srname)
     call assert(all(x(loc)), 'X(LOC) is all TRUE', srname)
@@ -2491,6 +2491,8 @@ function linspace_r(xstart, xstop, n) result(x)
     x(n) = xstop
 end if
 
+write(*, *) 'DEBUG: In LINSPACE_R, XSTART = ', xstart, ', XSTOP = ', xstop, ', N = ', n, ', X = ', x
+
 !====================!
 !  Calculation ends  !
 !====================!
@@ -2524,6 +2526,10 @@ function linspace_i(xstart, xstop, n) result(x)
 
 x = nint(linspace_r(real(xstart, RP), real(xstop, RP), n), IK)  ! Rounded to the closest integer.
 
+write(*,*) 'DEBUG: In LINSPACE_I - - - ', nint(1.0_RP, IK), nint(2.0_RP, IK), nint([1.0_RP, 2.0_RP], IK)
+
+write(*, *) 'DEBUG: In LINSPACE_I, XSTART = ', xstart, ', XSTOP = ', xstop, ', N = ', n, ', X = ', x
+
 !====================!
 !  Calculation ends  !
 !====================!

fortran/tests/makefiles/Makefile.common

@@ -92,7 +92,7 @@ endif
 
 # Define the compiler-dependent "fast flags", which will be used when FFLAGS is -fast.
 AFF := -O4
-DFF := -O4 -Ofast -ffast-math  # As of AOCC 4.2, -Ofast implies -O3, but it is not clear whether it implies -ffast-math
+DFF := -O3 -Ofast -ffast-math  # As of AOCC 4.2, -Ofast implies -O3, but it is not clear whether it implies -ffast-math; -O4 and -O3 are equivalent for AOCC 5.1
 FFF := -O3 -ffast-math  # Suggested by flang 20.1.7
 GFF := -Ofast  # -Ofast implies -O3 and -ffast-math
 MFF := -O3 -ffast-math  # Suggested by AOMP 22.0-2 when running `amdflang --help | grep fast`
@@ -170,7 +170,7 @@ CHCKTST := $(TOOLS_DIR)/checktest
 # Define the tests.
 ######################################################################################
 # Decide whether to test QP, i.e., REAL128.
-# Classic Flang 17.0 and nvfortran 24.1 do not support REAL128;
+# nvfortran 26.1 do not support REAL128;
 # AOCC 4.2 Flang complains about a symbol lookup error: undefined symbol: "fort_rnumq_i8";
 # AOCC 5.0 Flang is buggy concerning `nint` with REAL128.
 TESTS_QP = atest gtest mtest ntest itest stest 9test xtest
@@ -1083,9 +1083,9 @@ source_%: $(SRC_DIRS)
 		-o -name "flint" \
 		-o -name "mlint" \
 		\) -exec rm {} \;  # Cleaning up; important!!!
-	# Classic Flang 17.0, Huawei Bisheng Flang 2.1.0, Arm Fortran Compiler version 23.10, and AOCC
-	# 4.2 are buggy concerning 0-dimensional arrays, and they report false positive out-bound
-	# indices. Thus preprocessing by rdsrc is needed. See
+	# Huawei Bisheng Flang 2.1.0, Arm Fortran Compiler version 23.10, and AOCC 5.1 Flang are buggy
+	# concerning 0-dimensional arrays, and they report false positive out-bound indices. Thus
+	# preprocessing by rdsrc is needed. See
 	# https://github.com/flang-compiler/flang/issues/1238
 	# Check it again when new versions are available. Make a test using
 	# https://github.com/zequipe/test_compiler/blob/master/test_solve.f90

fortran/tests/tools/rdsrc

@@ -1,9 +1,8 @@
 #!/usr/bin/env bash
-# This script pre-processes the Fortran source code for Classic Flang 17.0, Huawei Bisheng flang
-# 2.1.0, Arm Fortran Compiler 23.1, and AOCC 4.2 flang, which raise a false positive error about
+# This script pre-processes the Fortran source code for Huawei Bisheng flang 2.1.0,
+# Arm Fortran Compiler 23.1, and AOCC 5.1 flang, which raise a false positive error about
 # out-bound subscripts when invoked with the -Mbounds flag.
 # See https://github.com/flang-compiler/flang/issues/1238 and
-# https://forums.developer.nvidia.com/t/bug-in-nvfortran-22-3-false-positive-of-out-bound-subscripts
 
 DIR="$(realpath "$1")"
 LINALG="$DIR/common/linalg.f90"