tests: Re-use Fedora tests

Related: rhbz#2061056

tests/build-gating-libomp.fmf

@@ -7,21 +7,14 @@ adjust:
       and trigger != build
     enabled: false
 
-  - because: "When testing SCL-ized LLVM, the collection must be enabled first"
-    environment+:
-      WITH_SCL: "scl enable llvm-toolset-13.0"
-    when: "collection == llvm-toolset-13.0"
-  - because: "When testing SCL-ized LLVM, the collection must be enabled first"
-    environment+:
-      WITH_SCL: "scl enable llvm-toolset-14.0"
-    when: "collection == llvm-toolset-14.0"
-
   - because: "libomp not supported in s390x"
     when: arch == s390x
     enabled: false
 
 discover:
     how: fmf
+    url: https://src.fedoraproject.org/rpms/clang.git
+    ref: rawhide
     test: libomp
 execute:
     how: tmt

tests/build-gating-pocl.fmf

@@ -1,32 +0,0 @@
-summary: PoCL clang tests for build/PR gating
-adjust:
-  - because: "Plan to be ran when either executed locally, or executed by CI system to gate a build or PR."
-    when: >-
-      trigger is defined
-      and trigger != commit
-      and trigger != build
-    enabled: false
-
-  - because: "PoCL is shipped with Fedora, not RHEL/CentOS"
-    when: >-
-      distro == rhel
-      or distro == centos
-    enabled: false
-
-discover:
-    how: fmf
-    test: pocl
-execute:
-    how: tmt
-prepare:
-    # Programs linked against pocl should be able to run without clang installed,
-    # so when we run the test we want to make sure clang is not installed to
-    # verify we haven't introduced an implicit dependency on clang.
-    - name: Drop clang
-      how: shell
-      script: |
-        dnf erase -y clang
-
-provision:
-  hardware:
-    memory: ">= 4 GiB"

tests/build-gating.fmf

@@ -1,13 +1,12 @@
 #
 # Build/PR gating tests for *LLVM 13*
 #
-# Compatible with various LLVM 13 distributions:
+# Imports and runs tests provided by Fedora LLVM git for the matching LLVM version.
 #
-#   * Fedora (ursine packages)
-#   * Centos 9 stream (ursine packages)
-#   * RHEL-9 (ursine packages)
-#   * RHEL-8 (Red Hat module)
-#   * RHEL-7 (software collection)
+# NOTE: *always* keep this file in sync with upstream, i.e. Fedora. Since we cannot "discover" a plan,
+# we must duplicate at least some part of upstream plan setup, like `adjust` or `provision`. Not necessarily
+# all steps, btu if we do need some of them here, let's focus on making changes in upstream first, to preserve
+# one source of truth. Once TMT learns to include whole plans, we could drop the copied content from here.
 #
 
 summary: Clang tests for build/PR gating
@@ -19,15 +18,6 @@ adjust:
       and trigger != build
     enabled: false
 
-  - because: "When testing SCL-ized LLVM, the collection must be enabled first"
-    environment+:
-      WITH_SCL: "scl enable llvm-toolset-13.0"
-    when: "collection == llvm-toolset-13.0"
-  - because: "When testing SCL-ized LLVM, the collection must be enabled first"
-    environment+:
-      WITH_SCL: "scl enable llvm-toolset-14.0"
-    when: "collection == llvm-toolset-14.0"
-
   # Unfortunately, TMT does not support more declarative approach, we need to run commands on our own.
   - because: "On RHEL, CRB must be enabled to provide rarer packages"
     prepare+:
@@ -50,6 +40,8 @@ adjust:
 discover:
     - name: clang-tests
       how: fmf
+      url: https://src.fedoraproject.org/rpms/clang.git
+      ref: rawhide
       filter: "tag:-not-in-default"
     - name: upstream-llvm-integration-testsuite
       how: fmf

tests/clang-format-diff/main.fmf

@@ -1,15 +0,0 @@
-summary: clang-format-diff
-test: "$WITH_SCL ./test.sh"
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require:
-      - clang-tools-extra
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require:
-      - llvm-toolset-13.0-clang-tools-extra
-    when: "collection == llvm-toolset-13.0"
-  - require:
-      - llvm-toolset-14.0-clang-tools-extra
-    when: "collection == llvm-toolset-14.0"

tests/clang-format-diff/test.sh

@@ -1,5 +0,0 @@
-#!/bin/sh -eux
-
-# Check that clang-format-diff is in PATH.
-# rhbz#1939018
-clang-format-diff -h

tests/fedora-flags/hello.c

@@ -1,5 +0,0 @@
-#include <stdio.h>
-
-void hello() {
-  printf("Hello World\n");
-}

tests/fedora-flags/hello.cpp

@@ -1,5 +0,0 @@
-#include <iostream>
-
-void hello() {
-  std::cout << "Hello World\n";
-}

tests/fedora-flags/main.c

@@ -1,6 +0,0 @@
-void hello();
-
-int main(int argc, char **argv) {
-  hello();
-  return 0;
-}

tests/fedora-flags/main.cpp

@@ -1,6 +0,0 @@
-void hello();
-
-int main(int argc, char **argv) {
-  hello();
-  return 0;
-}

tests/fedora-flags/main.fmf

@@ -1,17 +0,0 @@
-summary: fedora-flags
-test: "$WITH_SCL ./test.sh"
-require:
-  - annobin
-  - clang
-  - redhat-rpm-config
-adjust:
-  - because: s390x does not have epel repo which is required to provide rpm macros
-    enabled: false
-    when: >-
-      distro == rhel-7
-      and arch == s390x
-
-  - because: "To enable rpm macros not available by default (e.g. build_cflags), epel-rpm-macros is needed"
-    require+:
-      - epel-rpm-macros
-    when: distro == rhel-7

tests/fedora-flags/test.sh

@@ -1,20 +0,0 @@
-#!/bin/sh -eux
-
-set pipefail
-
-cflags=`rpm -D '%toolchain clang' -E %{build_cflags}`
-cxxflags=`rpm -D '%toolchain clang' -E %{build_cxxflags}`
-ldflags=`rpm -D '%toolchain clang' -E %{build_ldflags}`
-
-
-# Test a c program
-clang $cflags -c hello.c -o hello.o
-clang $cflags -c main.c -o main.o
-clang $ldflags -o hello main.o hello.o
-./hello | grep "Hello World"
-
-# Test a cxx program
-clang++ $cxxflags -c hello.cpp -o hello-cpp.o
-clang++ $cxxflags -c main.cpp -o main-cpp.o
-clang++ $ldflags -o hello-cpp main-cpp.o hello-cpp.o
-./hello-cpp | grep "Hello World"

tests/libomp/main.fmf

@@ -1,36 +0,0 @@
-# TODO: get fitting summary - what's the purpose of this test? Comment from the STI version says:
-#
-# We want to make sure libomp is not already present on the system to ensure
-# that clang pulls in the correct libomp dependencies when it is installed.
-summary: libomp tests
-# This test requires a special preparation, see `/tests/tests-libomp` plan. As such,
-# it shouldn't be part of the `/tests/default` plan.
-tag:
-  - not-in-default
-test: "$WITH_SCL ./test.sh"
-adjust:
-  - because: "libomp is not supported in s390x"
-    when: arch == s390x
-    enabled: false
-
-  # Common requirements when LLVM is not SCL-ized
-  - require:
-      - clang
-      - clang-libs
-      - libomp
-      - libomp-devel
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require:
-      - llvm-toolset-13.0-clang
-      - llvm-toolset-13.0-clang-libs
-      - llvm-toolset-13.0-libomp
-      - llvm-toolset-13.0-libomp-devel
-    when: "collection == llvm-toolset-13.0"
-  - require:
-      - llvm-toolset-14.0-clang
-      - llvm-toolset-14.0-clang-libs
-      - llvm-toolset-14.0-libomp
-      - llvm-toolset-14.0-libomp-devel
-    when: "collection == llvm-toolset-14.0"

tests/libomp/openmp-compile-link-test.c

@@ -1,8 +0,0 @@
-#include <omp.h>
-#include <stdio.h>
-
-int main(int argc, char **argv) {
-  int nthreads = omp_get_num_threads();
-  printf("Num Threads: %d\n", nthreads);
-  return 0;
-}

tests/libomp/test.sh

@@ -1,7 +0,0 @@
-#!/bin/bash
-
-set -exo pipefail
-
-clang -fopenmp openmp-compile-link-test.c
-
-./a.out | grep "Num Threads: 1"

tests/llvm-test-suite/main.fmf

@@ -1,18 +0,0 @@
-# TODO: once llvm-test-suite is converted to TMT, we can just link the test from plan.
-summary: Run tests from llvm-test-suite package
-
-adjust:
-  - because: "llvm-test-suite is available for Fedora, not RHEL/CentOS"
-    when: >-
-      distro == rhel
-      or distro == centos
-    enabled: false
-
-test: "$WITH_SCL ./test.sh"
-
-require:
-  - git
-  - clang
-  - ninja-build
-  - llvm-test-suite
-duration: 1h

tests/llvm-test-suite/test.sh

@@ -1,7 +0,0 @@
-#!/bin/sh -eux
-
-# TODO: tmt does not support a remote git repo as a requirement, one has to clone it "manually".
-
-git clone --depth 1 https://src.fedoraproject.org/rpms/llvm-test-suite.git llvm-test-suite
-cd llvm-test-suite/tests/test-suite
-./runtest.sh

tests/openmp-rpm/main.fmf

@@ -1,30 +0,0 @@
-summary: Test build a simple RPM package to ensure that -fopenmp works
-test: "$WITH_SCL ./runtest.sh"
-require:
-  - rpm-build
-adjust:
-  - because: "libomp not supported in s390x"
-    when: arch == s390x
-    enabled: false
-
-  - because: "Use yum in RHEL < 8"
-    require+:
-      - yum-utils
-    environment+:
-      BUILDDEP_CMD: "yum-builddep"
-    when: distro < rhel-8
-
-  - because: "Use dnf in RHEL >= 8, Fedora and CentOS"
-    require+:
-      - dnf-plugins-core
-    environment+:
-      BUILDDEP_CMD: "dnf builddep"
-    when: distro >= rhel-8 or distro != rhel
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-build
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-build
-    when: "collection == llvm-toolset-14.0"

tests/openmp-rpm/runtest.sh

@@ -1,6 +0,0 @@
-#!/bin/bash
-
-set -ex
-
-${BUILDDEP_CMD} -y test.spec
-rpmbuild --define '_sourcedir .' --define '_builddir .' -bb test.spec

tests/openmp-rpm/test.c

@@ -1,7 +0,0 @@
-int main(int argc, char **argv) {
-  int res = 1;
-#pragma omp parallel
-#pragma omp single
-  res = 0;
-  return res;
-}

tests/openmp-rpm/test.spec

@@ -1,36 +0,0 @@
-%global toolchain clang
-%{?scl:%global scl_prefix %{scl}-}
-
-Name: test
-Version: 1
-Release: 1
-Summary: Test package for checking that RPM packages using -fopenmp build correctly
-License: MIT
-
-BuildRequires: %{?scl_prefix}clang
-BuildRequires: %{?scl_prefix}libomp
-
-Source0: test.c
-
-%description
-clang was adding RUNPATH to binaries that use OpenMP, and since RUNPATH
-is prohibited in Fedora builds, this was causing packages using clang
-and OpenMP to fail to build.
-
-References:
-https://fedoraproject.org/wiki/Changes/Broken_RPATH_will_fail_rpmbuild
-https://github.com/llvm/llvm-project/commit/9b9d08111b618d74574ba03e5cc3d752ecc56f55
-
-%build
-clang ${CFLAGS} -c %{SOURCE0} -o test.o
-clang ${LDFLAGS} -fopenmp test.o -o main
-
-%check
-./main
-
-%install
-install -d %{buildroot}%{_bindir}
-install main %{buildroot}%{_bindir}
-
-%files
-%{_bindir}/main

tests/pocl/main.fmf

@@ -1,24 +0,0 @@
-# TODO REVIEW: get fitting summary - what's the purpose of this test? Comment from the STI version says:
-#
-# This is separate from tests.yml because we want to run the tests without
-# clang installed.
-summary: pocl
-
-adjust:
-  - because: "PoCL is shipped with Fedora, not RHEL/CentOS"
-    when: >-
-      distro == rhel
-      or distro == centos
-    enabled: false
-
-# This test requires a special preparation, see `/tests/tests-pocl` plan. As such,
-# it shouldn't be part of the `/tests/default` plan.
-tag:
-  - not-in-default
-# rhbz#1582884
-test: "$WITH_SCL ./test.sh"
-require:
-  - git
-  - ocl-icd-devel
-  - pocl
-  - gcc

tests/pocl/test.sh

@@ -1,7 +0,0 @@
-#!/bin/sh -eux
-
-# TODO: tmt does not support a remote git repo as a requirement, one has to clone it "manually".
-
-git clone --depth 1 https://src.fedoraproject.org/rpms/pocl.git pocl
-cd pocl/tests/simple-opencl-no-clang
-./runtest.sh

tests/ppc64le-long-double/main.fmf

@@ -1,31 +0,0 @@
-summary: Test that gcc and clang use the same long double format on ppc64le
-test: $WITH_SCL ./runtest.sh
-duration: 1h
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-    when: "collection is not defined"
-
-  - because: "Fedora CI runs in x86_64 only, emulate with qemu and mock"
-    require+:
-    - qemu-user-static
-    - mock
-    test: ./runtest-fedora.sh
-    when: distro == fedora and arch == x86_64
-    continue: false
-
-  - enabled: false
-    when: arch != ppc64le
-
-  - require+:
-    - gcc
-    when: distro != fedora
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-    when: "collection == llvm-toolset-14.0"

tests/ppc64le-long-double/runtest-fedora.sh

@@ -1,14 +0,0 @@
-set -e
-
-fedora_release=`rpm -E %{fedora}`
-mock_root=fedora-$fedora_release-ppc64le
-triple=ppc64le-redhat-linux
-
-mock -r $mock_root --isolation=simple --install gcc
-gcc_output=$(mock -r $mock_root --isolation=simple -q --shell gcc -E -dM -x c /dev/null | grep -e __LONG_DOUBLE_IEEE128__ -e __LONG_DOUBLE_IBM128__)
-clang_output=$(clang -target $triple  -E -dM -x c /dev/null | grep -e __LONG_DOUBLE_IEEE128__ -e __LONG_DOUBLE_IBM128__)
-
-echo "gcc:   $gcc_output"
-echo "clang: $clang_output"
-
-test "$gcc_output" = "$clang_output"

tests/ppc64le-long-double/runtest.sh

@@ -1,9 +0,0 @@
-set -e
-
-gcc_output=$(gcc -E -dM -x c /dev/null | grep -e __LONG_DOUBLE_IEEE128__ -e __LONG_DOUBLE_IBM128__)
-clang_output=$(clang -E -dM -x c /dev/null | grep -e __LONG_DOUBLE_IEEE128__ -e __LONG_DOUBLE_IBM128__)
-
-echo "gcc:   $gcc_output"
-echo "clang: $clang_output"
-
-test "$gcc_output" = "$clang_output"

tests/rhbz_1647130/main.fmf

@@ -1,19 +0,0 @@
-summary: RHBZ1647130
-test: "$WITH_SCL ./test.sh"
-require: []
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-      - clang-analyzer
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-      - llvm-toolset-13.0-clang-analyzer
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-      - llvm-toolset-14.0-clang-analyzer
-    when: "collection == llvm-toolset-14.0"

tests/rhbz_1647130/test.sh

@@ -1,8 +0,0 @@
-#!/bin/sh -eux
-
-tmp_cpp=`mktemp -t XXXXX.cpp`
-tmp_dir=`mktemp -d`
-echo 'int main(int argc, char*argv[]) { while(argc--) new int(); return 0; }' > $tmp_cpp
-scan-build -o $tmp_dir clang++ -c $tmp_cpp -o /dev/null
-(scan-view --no-browser $tmp_dir/* & WPID=$! && sleep 10s && kill $WPID)
-

tests/rhbz_1657544/from_chars.cpp

@@ -1,15 +0,0 @@
-#include <charconv>
-#include <iostream>
-#include <cstring>
-
-using namespace std;
-
-int main(int argc, char **argv)
-{
-	size_t r=0;
-	const char *begin = argv[1];
-	const char *end = begin + strlen(begin);
-	from_chars(begin, end, r);
-	cout << r << '\n';
-	return 0;
-}

tests/rhbz_1657544/main.fmf

@@ -1,16 +0,0 @@
-summary: RHBZ1657544
-test: "$WITH_SCL ./test.sh"
-require: []
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-    when: "collection == llvm-toolset-14.0"

tests/rhbz_1657544/test.sh

@@ -1,4 +0,0 @@
-#!/bin/sh -eux
-
-clang++ from_chars.cpp
-./a.out 100 | grep 100

tests/rhbz_482491/main.fmf

@@ -1,17 +0,0 @@
-summary: rhbz-482491
-test: "$WITH_SCL ./test.sh"
-require:
-  - libgcc
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-    when: "collection == llvm-toolset-14.0"

tests/rhbz_482491/test.sh

@@ -1,3 +0,0 @@
-#!/bin/sh -eux
-
-find /usr -name 'libgcc_s.so*' && echo "int main(){}" | clang -v -x c -

tests/toolchains/hello.c

@@ -1,5 +0,0 @@
-#include<stdio.h>
-int main(int argc, char **argv) {
-  printf("Hello World\n");
-  return 0;
-}

tests/toolchains/hello.cpp

@@ -1,5 +0,0 @@
-#include <iostream>
-int main(int argc, char **argv) {
-  std::cout << "Hello World\n";
-  return 0;
-}

tests/toolchains/main.fmf

@@ -1,55 +0,0 @@
-# TODO REVIEW: better summary
-summary: ""
-test: "$WITH_SCL ./test.sh"
-require:
-  - glibc-static
-  - yum-utils
-  # This require EPEL/CRB to be enabled on RHEL
-  - libstdc++-static
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-      - compiler-rt
-      - lld
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-      - llvm-toolset-13.0-compiler-rt
-      - llvm-toolset-13.0-lld
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-      - llvm-toolset-14.0-compiler-rt
-      - llvm-toolset-14.0-lld
-    when: "collection == llvm-toolset-14.0"
-
-    # lld not supported in s390x or ppc64. If any lld package was added to
-    # requirements, remove it.
-  - require-:
-      - lld
-      - llvm-toolset-13.0-lld
-      - llvm-toolset-14.0-lld
-    when: arch == s390x or arch == ppc64
-
-  - environment+:
-      CXXLIBS: "libc++"
-    require+:
-      - libcxx-devel
-      - libcxx-static
-    when: "distro == fedora"
-    because: testing against libcxx package in Fedora
-
-  - environment+:
-      CXXLIBS: "libstdc++"
-    require+:
-      - libstdc++
-    when: >-
-      distro == rhel
-      or distro == centos
-    because: testing against libstdc++ package in RHEL as libcxx is not shipped with RHEL
-
-# TODO REVIEW: are these all requirements? test.sh seems to run quite a lot of stuff, looks like we
-# need more packages from LLVM family.

tests/toolchains/test.sh

@@ -1,102 +0,0 @@
-#!/bin/sh -eux
-
-set pipefail
-
-if [ -z "${CXXLIBS:-}" ]; then
-  echo "CXXLIBS variable is a required input but it's not specified!"
-  echo "Test metadata should have picked a proper value, depending on distro."
-  exit 1
-fi
-
-status=0
-
-test_toolchain() {
-
-    toolchain=$@
-    args=""
-
-    while [ $# -gt 0 ]; do
-        case $1 in
-            clang)
-                compiler=$1
-                src=hello.c
-                ;;
-            clang++)
-                compiler=$1
-                src=hello.cpp
-                ;;
-            compiler-rt)
-                args="$args -rtlib=$1"
-                ;;
-            libc++)
-                args="$args -stdlib=$1"
-                ;;
-            libstdc++)
-                args="$args -stdlib=$1"
-                ;;
-            lld)
-                args="$args -fuse-ld=$1"
-                ;;
-            *)
-                args="$args $1"
-                ;;
-        esac
-    shift
-    done
-
-    cmd="$compiler $args $src"
-    rm -f a.out
-    echo "* $toolchain"
-    echo "  command: $cmd"
-    if $cmd && ./a.out | grep -q 'Hello World'; then
-        echo "  PASS"
-    else
-        echo "  FAIL"
-        status=1
-    fi
-}
-
-clang --version
-# Repoquery is needed instead yum info for compatibility with RHEL-7
-repoquery -i --installed $(rpm -qf $(which clang)) | grep ^Source
-echo ""
-
-for compiler in clang clang++; do
-    for rtlib in "" compiler-rt; do
-        for linker in "" lld; do
-            for cxxlib in "" $CXXLIBS; do
-                if [ "$compiler" = "clang" -a -n "$cxxlib" ]; then
-                    continue
-                fi
-                for args in "" -static; do
-                    # Skip known failures
-                    # TODO: Fix these
-                    if [[ "$args" = "-static" && "$rtlib" = "compiler-rt" ]]; then
-                        continue
-                    fi
-
-                    # Static libc++ needs -pthread
-                    if [[ "$args" = "-static" && "$cxxlib" = "libc++" ]]; then
-                      args="$args -pthread"
-                    fi
-
-                    # lld is not supported in s390x and ppc64
-                    if [[ "$(uname -m)" = "s390x" || "$(uname -m)" = "ppc64" ]] \
-                        && [[ "$linker" = "lld" ]];
-                    then
-                      continue
-                    fi
-
-                    # compiler-rt does not provide builtins for s390x
-                    if [[ "$(uname -m)" = "s390x" && "$rtlib" = "compiler-rt" ]]; then
-                      continue
-                    fi
-
-                    test_toolchain $compiler $rtlib $linker $cxxlib $args
-                done
-            done
-        done
-    done
-done
-
-exit $status

tests/use-dwarf4-by-default/main.fmf

@@ -1,20 +0,0 @@
-summary: Test that clang uses DWARFv4 by default
-test: "$WITH_SCL ./test.sh"
-require:
-  - libgcc
-adjust:
-  # Common requirements when LLVM is not SCL-ized
-  - require+:
-      - clang
-      - llvm
-    when: "collection is not defined"
-
-  # Requirements for SCL-ized LLVM
-  - require+:
-      - llvm-toolset-13.0-clang
-      - llvm-toolset-13.0-llvm
-    when: "collection == llvm-toolset-13.0"
-  - require+:
-      - llvm-toolset-14.0-clang
-      - llvm-toolset-14.0-llvm
-    when: "collection == llvm-toolset-14.0"

tests/use-dwarf4-by-default/test.sh

@@ -1,7 +0,0 @@
-#!/bin/sh -eux
-
-echo "int main(){ return 0; }" | clang -g -v -x c - 2> build.log
-# Make sure that clang is using the expected flag to use DWARF 4
-grep -q "\-dwarf-version=4" build.log
-# Inspect the binary to double check expected DWARF version
-llvm-dwarfdump a.out | grep -i version | grep 0x0004