Adjust code coverage workflow

Extract lcov setup to a stand-alone file. Remove obsolete check on
gcov symbols. Forward code coverage flags to ccache to regenerate
.gcno files when building CUDA object files.

cmake/FindCUDACompilerNVCC.cmake

@@ -50,6 +50,8 @@ target_compile_options(
   $<$<CONFIG:Coverage>:-Xptxas=-O3 -Xcompiler=-Og,-g,--coverage,-fprofile-abs-path>
   $<$<CONFIG:RelWithAssert>:-Xptxas=-O3 -Xcompiler=-O3,-g>
   $<$<BOOL:${CMAKE_OSX_SYSROOT}>:-Xcompiler=-isysroot;-Xcompiler=${CMAKE_OSX_SYSROOT}>
+  # workaround for https://github.com/espressomd/espresso/issues/4943
+  $<$<BOOL:${ESPRESSO_BUILD_WITH_CCACHE}>:$<$<CONFIG:Coverage>:--coverage -fprofile-abs-path>>
 )
 
 function(espresso_add_gpu_library)

maintainer/CI/build_cmake.sh

@@ -261,9 +261,8 @@ end "BUILD"
 # library. See details in https://github.com/espressomd/espresso/issues/2249
 # Can't do this check on CUDA though because nvcc creates a host function
 # that just calls exit() for each device function, and can't do this with
-# coverage because gcov 9.0 adds code that calls exit(), and can't do this
 # with walberla because the library calls exit() in assertions.
-if [[ "${with_coverage}" == false && ( "${with_cuda}" == false || "${with_cuda_compiler}" != "nvcc" ) && "${with_walberla}" != "true" ]]; then
+if [[ ( "${with_cuda}" == false || "${with_cuda_compiler}" != "nvcc" ) && "${with_walberla}" != "true" ]]; then
     if nm -o -C $(find . -name '*.so') | grep '[^a-z]exit@@GLIBC'; then
         echo "Found calls to exit() function in shared libraries."
         exit 1
@@ -355,20 +354,7 @@ if [ "${with_coverage}" = true ] || [ "${with_coverage_python}" = true ]; then
     if [ "${with_coverage}" = true ]; then
         echo "Running lcov and gcov..."
         codecov_opts="${codecov_opts} --gcov"
-        lcov --gcov-tool "${GCOV:-gcov}" \
-             --quiet \
-             --ignore-errors graph,mismatch,mismatch,gcov,unused \
-             --directory . \
-             --filter brace,blank,range,region \
-             --capture \
-             --rc lcov_json_module="JSON::XS" \
-             --exclude "/usr/*" \
-             --exclude "$(realpath .)/_deps/*" \
-             --exclude "$(realpath .)/src/python/espressomd/*" \
-             --exclude "$(realpath "${srcdir}")/src/walberla_bridge/src/*/generated_kernels/*" \
-             --exclude "$(realpath "${srcdir}")/libs/*" \
-             --exclude "*/tmpxft_*cudafe1.stub.*" \
-             --output-file coverage.info
+        ./run_lcov.sh coverage.info
     fi
     if [ "${with_coverage_python}" = true ]; then
         echo "Running python3-coverage..."

maintainer/CI/run_lcov.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env sh
+#
+# Copyright (C) 2017-2024 The ESPResSo project
+#
+# This file is part of ESPResSo.
+#
+# ESPResSo is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ESPResSo is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+set -e
+
+output="${1:-coverage.info}"
+bindir="$(realpath .)"
+srcdir="$(sed -nr "s/^ESPResSo_SOURCE_DIR:STATIC=(.+)/\1/p" "${bindir}/CMakeCache.txt")"
+
+if [ "${srcdir}" = "" ]; then
+  echo "Cannot extract ESPResSo_SOURCE_DIR variable from the CMake cache" >&2
+  exit 2
+fi
+
+lcov --gcov-tool "${GCOV:-gcov}" \
+     --quiet \
+     --ignore-errors graph,mismatch,mismatch,gcov,unused \
+     --directory . \
+     --filter brace,blank,range,region \
+     --capture \
+     --rc lcov_json_module="JSON::XS" \
+     --exclude "/usr/*" \
+     --exclude "*/tmpxft_*cudafe1.stub.*" \
+     --exclude "${bindir}/_deps/*" \
+     --exclude "${bindir}/src/python/espressomd/*" \
+     --exclude "${srcdir}/src/walberla_bridge/src/*/generated_kernels/*" \
+     --exclude "${srcdir}/libs/*" \
+     --output-file "${output}"