[flang/flang-rt] Add -isysroot flag only to tests really requiring

-isysroot flag was added to all tests, but it makes
Driver/darwin-version.f90 failed.

In fact, only a few tests need -isysroot flag. So, -isysroot flag
is now eliminated from the substitution `%flang`, and a new substitution
`%isysroot` has been introduced.

Moreover, Integration/iso-fortran-binding.cpp invokes clang++
via a shell script, which makes it hard to add -isysroot flag.
So, it is refactored.

Author: parabola94

flang-rt/test/Driver/ctofortran.f90

@@ -2,8 +2,8 @@
 ! UNSUPPORTED: offload-cuda
 
 ! RUN: split-file %s %t
-! RUN: %clang -I"%include/flang" -c %t/cfile.c -o %t/cfile.o
-! RUN: %flang -L"%libdir" %t/ffile.f90 %t/cfile.o -o %t/ctofortran
+! RUN: %clang %isysroot -I"%include/flang" -c %t/cfile.c -o %t/cfile.o
+! RUN: %flang %isysroot -L"%libdir" %t/ffile.f90 %t/cfile.o -o %t/ctofortran
 ! RUN: env LD_LIBRARY_PATH="$LD_LIBRARY_PATH:%libdir" %t/ctofortran | FileCheck %s
 
 !--- ffile.f90

flang-rt/test/Runtime/no-cpp-dep.c

@@ -7,7 +7,7 @@ UNSUPPORTED: system-windows
 UNSUPPORTED: offload-cuda
 
 RUN: %if system-aix %{ export OBJECT_MODE=64 %}
-RUN: %cc -std=c99 %s -I%include -L"%libdir" -lflang_rt.runtime -lm \
+RUN: %cc -std=c99 %s %isysroot -I%include -L"%libdir" -lflang_rt.runtime -lm \
 RUN: %if system-aix %{-lpthread %}
 RUN: rm a.out
 */

flang-rt/test/lit.cfg.py

@@ -62,25 +62,24 @@ def shjoin(args, sep=" "):
 # lit writes a '.lit_test_times.txt' file into this directory.
 config.test_exec_root = config.flang_rt_binary_test_dir
 
-# On MacOS, -isysroot is needed to build binaries.
+# On MacOS, some tests need -isysroot to build binaries.
 isysroot_flag = []
 if config.osx_sysroot:
     isysroot_flag = ["-isysroot", config.osx_sysroot]
+config.substitutions.append(("%isysroot", " ".join(isysroot_flag)))
 
 tools = [
     ToolSubst(
         "%flang",
         command=config.flang,
-        extra_args=isysroot_flag,
         unresolved="fatal",
     ),
     ToolSubst(
         "%clang",
         command=FindTool("clang"),
-        extra_args=isysroot_flag,
         unresolved="fatal",
     ),
-    ToolSubst("%cc", command=config.cc, extra_args=isysroot_flag, unresolved="fatal"),
+    ToolSubst("%cc", command=config.cc, unresolved="fatal"),
 ]
 llvm_config.add_tool_substitutions(tools)
 

flang/test/Integration/iso-fortran-binding.cpp

@@ -1,9 +1,9 @@
+// REQUIRES: clang
 // UNSUPPORTED: system-windows
-// RUN: split-file %s %t
-// RUN: chmod +x %t/runtest.sh
-// RUN: %t/runtest.sh %t %t/cppfile.cpp %flang | FileCheck %s
+// RUN: rm -rf %t && mkdir %t
+// RUN: %clangxx %isysroot -I %include/flang %s -o %t/a.out
+// RUN: %t/a.out | FileCheck %s
 
-//--- cppfile.cpp
 extern "C" {
 #include "ISO_Fortran_binding.h"
 }
@@ -15,19 +15,3 @@ int main() {
 }
 
 // CHECK: PASS
-// clang-format off
-//--- runtest.sh
-#!/bin/bash
-TMPDIR=$1
-CPPFILE=$2
-FLANG=$3
-BINDIR=`dirname $FLANG`
-CPPCOMP=$BINDIR/clang++
-if [ -x $CPPCOMP ]
-then
-  $CPPCOMP $CPPFILE -o $TMPDIR/a.out
-  $TMPDIR/a.out # should print "PASS"
-else
-  # No clang compiler, just pass by default
-  echo "PASS"
-fi

flang/test/Integration/lit.local.cfg

@@ -0,0 +1,13 @@
+from lit.llvm import llvm_config
+
+llvm_config.use_clang(required=False)
+if llvm_config.config.clang:
+    config.available_features.add("clang")
+    clangxx = next((subst for subst in llvm_config.config.substitutions
+        if "clangxx" in subst[0]), None)
+    config.substitutions.append(clangxx)
+
+# Include path for C headers that define Flang's Fortran ABI.
+config.substitutions.append(
+    ("%include", os.path.join(config.flang_source_dir, "include"))
+)

flang/test/lit.cfg.py

@@ -118,10 +118,11 @@
                 "PATH", config.flang_llvm_tools_dir, append_path=True
             )
 
-# On MacOS, -isysroot is needed to build binaries.
+# On MacOS, some tests need -isysroot to build binaries.
 isysroot_flag = []
 if config.osx_sysroot:
     isysroot_flag = ["-isysroot", config.osx_sysroot]
+config.substitutions.append(("%isysroot", " ".join(isysroot_flag)))
 
 # Check for DEFAULT_SYSROOT, because when it is set -isysroot has no effect.
 if config.default_sysroot:
@@ -133,7 +134,6 @@
     ToolSubst(
         "%flang",
         command=FindTool("flang"),
-        extra_args=isysroot_flag,
         unresolved="fatal",
     ),
     ToolSubst(

flang/test/lit.site.cfg.py.in

@@ -6,10 +6,12 @@ import lit.util
 config.llvm_tools_dir = lit_config.substitute("@LLVM_TOOLS_DIR@")
 config.llvm_shlib_dir = lit_config.substitute(path(r"@SHLIBDIR@"))
 config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
+config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.target_triple = "@LLVM_TARGET_TRIPLE@"
 config.llvm_target_triple_env = "@LLVM_TARGET_TRIPLE_ENV@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.errc_messages = "@LLVM_LIT_ERRC_MESSAGES@"
+config.flang_source_dir = "@FLANG_SOURCE_DIR@"
 config.flang_obj_root = "@FLANG_BINARY_DIR@"
 config.flang_tools_dir = lit_config.substitute("@FLANG_TOOLS_DIR@")
 config.flang_intrinsic_modules_dir = "@FLANG_INTRINSIC_MODULES_DIR@"