Add coverage and gcovr reporting support

Add gcovr pip install and cmake targets and configurations for running
coverage and collecting and processing the results.

Author: steve-downey

CMakeLists.txt

@@ -55,3 +55,13 @@ install(
   FILES ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_PROJECT_NAME}Config.cmake
         ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_PROJECT_NAME}ConfigVersion.cmake
   DESTINATION ${INSTALL_CONFIGDIR})
+
+# Coverage
+configure_file("cmake/gcovr.cfg.in" gcovr.cfg @ONLY)
+
+add_custom_target(
+  process_coverage
+  WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+  COMMENT "Running gcovr to process coverage results"
+  COMMAND mkdir -p coverage
+  COMMAND gcovr --config gcovr.cfg .)

Makefile

@@ -27,12 +27,12 @@ export
 ifeq ($(strip $(TOOLCHAIN)),)
 	_build_name?=build-system/
 	_build_dir?=.build/
-	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
+	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan;Gcov"
 	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/toolchain.cmake
 else
 	_build_name?=build-$(TOOLCHAIN)
 	_build_dir?=.build/
-	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan"
+	_configuration_types?="RelWithDebInfo;Debug;Tsan;Asan;Gcov"
 	_cmake_args=-DCMAKE_TOOLCHAIN_FILE=$(CURDIR)/etc/$(TOOLCHAIN)-toolchain.cmake
 endif
 
@@ -152,6 +152,10 @@ lint: venv
 lint: ## Run all configured tools in pre-commit
 	$(PRE_COMMIT) run -a
 
+coverage: venv
+	$(MAKE) CONFIG=Gcov test
+	$(ACTIVATE) cmake --build $(_build_path)  --config $(CONFIG) --target process_coverage
+
 # Help target
 .PHONY: help
 help: ## Show this help.

cmake/gcovr.cfg.in

@@ -0,0 +1,11 @@
+root = @CMAKE_SOURCE_DIR@
+cobertura = @CMAKE_BINARY_DIR@/coverage/cobertura.xml
+sonarqube = @CMAKE_BINARY_DIR@/coverage/sonarqube.xml
+html-details = @CMAKE_BINARY_DIR@/coverage/coverage.html
+gcov-executable = @GCOV_EXECUTABLE@
+gcov-parallel = yes
+html-theme = github.dark-blue
+html-self-contained = yes
+print-summary = yes
+filter = .*/Beman/Optional26/.*
+exclude = .*\.t\.cpp

etc/clang-16-toolchain.cmake

@@ -2,5 +2,8 @@ include_guard(GLOBAL)
 
 set(CMAKE_C_COMPILER clang-16)
 set(CMAKE_CXX_COMPILER clang++-16)
+set(GCOV_EXECUTABLE
+    "llvm-cov-16 gcov"
+    CACHE STRING "GCOV executable" FORCE)
 
 include("${CMAKE_CURRENT_LIST_DIR}/clang-flags.cmake")

etc/clang-17-toolchain.cmake

@@ -2,5 +2,8 @@ include_guard(GLOBAL)
 
 set(CMAKE_C_COMPILER clang-17)
 set(CMAKE_CXX_COMPILER clang++-17)
+set(GCOV_EXECUTABLE
+    "llvm-cov-17 gcov"
+    CACHE STRING "GCOV executable" FORCE)
 
 include("${CMAKE_CURRENT_LIST_DIR}/clang-flags.cmake")

etc/clang-18-toolchain.cmake

@@ -2,5 +2,8 @@ include_guard(GLOBAL)
 
 set(CMAKE_C_COMPILER clang-18)
 set(CMAKE_CXX_COMPILER clang++-18)
+set(GCOV_EXECUTABLE
+    "llvm-cov-18 gcov"
+    CACHE STRING "GCOV executable" FORCE)
 
 include("${CMAKE_CURRENT_LIST_DIR}/clang-flags.cmake")

etc/clang-19-toolchain.cmake

@@ -2,5 +2,8 @@ include_guard(GLOBAL)
 
 set(CMAKE_C_COMPILER clang-19)
 set(CMAKE_CXX_COMPILER clang++-19)
+set(GCOV_EXECUTABLE
+    "llvm-cov-19 gcov"
+    CACHE STRING "GCOV executable" FORCE)
 
 include("${CMAKE_CURRENT_LIST_DIR}/clang-flags.cmake")

etc/clang-flags.cmake

@@ -21,3 +21,9 @@ set(CMAKE_CXX_FLAGS_TSAN
 set(CMAKE_CXX_FLAGS_ASAN
     "-O3 -g -DNDEBUG -fsanitize=address,undefined,leak"
     CACHE STRING "C++ ASAN Flags" FORCE)
+set(CMAKE_CXX_FLAGS_GCOV
+    "-O0 -fno-inline -g --coverage"
+    CACHE STRING "C++ GCOV Flags" FORCE)
+set(CMAKE_LINKER_FLAGS_GCOV
+    "--coverage"
+    CACHE STRING "Linker GCOV Flags" FORCE)

etc/gcc-11-toolchain.cmake

@@ -4,3 +4,6 @@ include("${CMAKE_CURRENT_LIST_DIR}/gcc-flags.cmake")
 
 set(CMAKE_C_COMPILER gcc-11)
 set(CMAKE_CXX_COMPILER g++-11)
+set(GCOV_EXECUTABLE
+    "gcov-11"
+    CACHE STRING "GCOV executable" FORCE)

etc/gcc-12-toolchain.cmake

@@ -4,3 +4,6 @@ include("${CMAKE_CURRENT_LIST_DIR}/gcc-flags.cmake")
 
 set(CMAKE_C_COMPILER gcc-12)
 set(CMAKE_CXX_COMPILER g++-12)
+set(GCOV_EXECUTABLE
+    "gcov-12"
+    CACHE STRING "GCOV executable" FORCE)