From dc3f4fd89b7700a920597630d43e6c2702c6cc46 Mon Sep 17 00:00:00 2001
From: Viktor Szakats <commit@vsz.me>
Date: Wed, 3 Sep 2025 16:48:49 +0200
Subject: [PATCH] autotools: make `--enable-code-coverage` support llvm/clang

Cherry-picked from #18468

Closes #18473
---
 configure.ac         |  5 ++---
 m4/curl-functions.m4 | 32 +++++++++++++++++++-------------
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/configure.ac b/configure.ac
index 3f02d037ef..6c33b561be 100644
--- a/configure.ac
+++ b/configure.ac
@@ -128,9 +128,6 @@ CURLVERSION=`$SED -ne 's/^#define LIBCURL_VERSION "\(.*\)".*/\1/p' ${srcdir}/inc
 XC_CHECK_PROG_CC
 CURL_ATOMIC
 
-dnl for --enable-code-coverage
-CURL_COVERAGE
-
 XC_AUTOMAKE
 AC_MSG_CHECKING([curl version])
 AC_MSG_RESULT($CURLVERSION)
@@ -523,6 +520,8 @@ dnl platform/compiler/architecture specific checks/flags
 dnl **********************************************************************
 
 CURL_CHECK_COMPILER
+dnl for --enable-code-coverage
+CURL_COVERAGE
 CURL_CHECK_NATIVE_WINDOWS
 
 curl_cv_wince='no'
diff --git a/m4/curl-functions.m4 b/m4/curl-functions.m4
index 83206dbc82..3640f0c84e 100644
--- a/m4/curl-functions.m4
+++ b/m4/curl-functions.m4
@@ -4290,25 +4290,31 @@ AC_DEFUN([CURL_COVERAGE],[
     AS_HELP_STRING([--enable-code-coverage], [Provide code coverage]),
     coverage="$enableval")
 
-  dnl if not gcc switch off again
-  AS_IF([ test "$GCC" != "yes" ], coverage="no" )
+  dnl if not gcc or clang switch off again
+  AS_IF([test "$compiler_id" != "GNU_C" -a "$compiler_id" != "CLANG" -a "$compiler_id" != "APPLECLANG"], coverage="no" )
   AC_MSG_RESULT($coverage)
 
   if test "x$coverage" = "xyes"; then
     curl_coverage_msg="enabled"
 
-    AC_CHECK_TOOL([GCOV], [gcov], [gcov])
-    if test -z "$GCOV"; then
-      AC_MSG_ERROR([needs gcov for code coverage])
-    fi
-    AC_CHECK_PROG([LCOV], [lcov], [lcov])
-    if test -z "$LCOV"; then
-      AC_MSG_ERROR([needs lcov for code coverage])
-    fi
-
     CPPFLAGS="$CPPFLAGS -DNDEBUG"
-    CFLAGS="$CFLAGS -O0 -g -fprofile-arcs -ftest-coverage"
-    LIBS="$LIBS -lgcov"
+    CFLAGS="$CFLAGS -O0 -g"
+
+    if test "$compiler_id" = "GNU_C"; then
+      AC_CHECK_TOOL([GCOV], [gcov], [gcov])
+      if test -z "$GCOV"; then
+        AC_MSG_ERROR([needs gcov for code coverage])
+      fi
+      AC_CHECK_PROG([LCOV], [lcov], [lcov])
+      if test -z "$LCOV"; then
+        AC_MSG_ERROR([needs lcov for code coverage])
+      fi
+      CFLAGS="$CFLAGS -ftest-coverage -fprofile-arcs"
+      LIBS="$LIBS -lgcov"
+    else
+      CFLAGS="$CFLAGS -fprofile-instr-generate -fcoverage-mapping"
+      LDFLAGS="$LDFLAGS -fprofile-instr-generate -fcoverage-mapping"
+    fi
   fi
 ])
 
-- 
2.47.3