Automatically select the coverage approach based on the compiler

Author: mdboom

.github/workflows/c-coverage.yml

@@ -46,7 +46,7 @@ jobs:
       run: ./configure --with-pydebug --with-openssl=$OPENSSL_DIR
     - name: Generate coverage report
       # Using "-j1" is important, or the Github Action runs out of memory
-      run: EXTRATESTOPTS=-j1 xvfb-run make coverage-report-llvm
+      run: EXTRATESTOPTS=-j1 xvfb-run make coverage-report
     - name: Publish coverage-report
       uses: JamesIves/github-pages-deploy-action@v4
       with:

Makefile.pre.in

@@ -38,6 +38,7 @@ CC=		@CC@
 CXX=		@CXX@
 MAINCC=		@MAINCC@
 LINKCC=		@LINKCC@
+CC_NAME=@CC_NAME@
 AR=		@AR@
 READELF=	@READELF@
 SOABI=		@SOABI@
@@ -648,9 +649,20 @@ profile-opt: profile-run-stamp
 	-rm -f profile-clean-stamp
 	$(MAKE) @DEF_MAKE_RULE@ CFLAGS_NODIST="$(CFLAGS_NODIST) $(PGO_PROF_USE_FLAG)" LDFLAGS_NODIST="$(LDFLAGS_NODIST)"
 
+.PHONY=coverage-report
+coverage-report:
+	@if [ $(CC_NAME) = "gcc" ]; then \
+		$(MAKE) coverage-report-lcov; \
+	elif [ $(CC_NAME) = "clang" ]; then \
+		$(MAKE) coverage-report-llvm; \
+	else \
+		echo "Coverage is not supported with the $(CC_NAME) compiler"; \
+		exit 1; \
+	fi
+
 # Compile and run with gcov
-.PHONY=coverage coverage-lcov coverage-report
-coverage:
+.PHONY=coverage-gcc coverage-lcov coverage-report-lcov
+coverage-gcc:
 	@echo "Building with support for coverage checking:"
 	$(MAKE) clean
 	$(MAKE) @DEF_MAKE_RULE@ CFLAGS="$(CFLAGS) -O0 -pg --coverage" LDFLAGS="$(LDFLAGS) --coverage"
@@ -686,7 +698,7 @@ coverage-lcov:
 	@echo
 
 # Force regeneration of parser and frozen modules
-coverage-report: regen-token regen-frozen
+coverage-report-lcov: regen-token regen-frozen
 	@ # build with coverage info
 	$(MAKE) coverage
 	@ # run tests, ignore failures
@@ -695,14 +707,9 @@ coverage-report: regen-token regen-frozen
 	$(MAKE) coverage-lcov
 
 # Compile and calculate coverage with llvm-cov
-.PHONY=check-clang coverage-llvm coverage-profdata coverage-report-llvm
-
-# Check whether the compiler is clang, and if not, error out.
-check-clang:
-	($(CC) --version | grep clang) || \
-	(echo "LLVM coverage only works with clang. Set CC=clang and CXX=clang++ and re-run ./configure"; exit 1)
+.PHONY=coverage-clang coverage-profdata coverage-report-llvm
 
-coverage-llvm: check-clang
+coverage-clang: 
 	@echo "Building with support for coverage checking:"
 	$(MAKE) clean
 	@ # Override CC rather than CFLAGS since these flags must come first
@@ -726,7 +733,7 @@ coverage-profdata:
 # into temporary directories created by tests.
 coverage-report-llvm: regen-token regen-importlib
 	@ # build with coverage info
-	$(MAKE) coverage-llvm
+	$(MAKE) coverage-clang
 	@ # run tests, ignore failures
 	LLVM_PROFILE_FILE=${PWD}/python%m.profraw $(TESTRUNNER) $(TESTOPTS) || true
 	@ # build llvm-cov report

Misc/NEWS.d/next/Build/2022-07-13-13-24-01.gh-issue-94759.dTLMod.rst

@@ -1,4 +1,2 @@
-A new Makefile target ``coverage-report-llvm`` will use ``clang`` and
-``llvm-cov`` to generate a coverage report. This provides more details about
-branch coverage and subexpressions than the existing ``gcc`` and ``lcov``
-based ``coverage-report``.
+The ``coverage-report`` Makefile target will now automatically use ``llvm-cov`` to generate a coverage report when using ``clang``.
+This provides more details about branch coverage and subexpressions than the existing ``gcc`` and ``lcov`` based ``coverage-report``.

configure

@@ -859,6 +859,9 @@ fi
 rm -f conftest.c conftest.out
 ])
 
+AC_SUBST(CC_NAME)
+CC_NAME=$ac_cv_cc_name
+
 # checks for UNIX variants that set C preprocessor variables
 # may set _GNU_SOURCE, __EXTENSIONS__, _POSIX_PTHREAD_SEMANTICS,
 # _POSIX_SOURCE, _POSIX_1_SOURCE, and more