[PATCH v2 1/1] riscv: treat clang separately in RVV compiler checks

[Yao Zihong]

From: Zihong Yao <zihong.plct@isrc.iscas.ac.cn>

Detect clang explicitly and apply compiler-specific version checks for
RVV support.

Signed-off-by: Zihong Yao <zihong.plct@isrc.iscas.ac.cn>
---
 sysdeps/riscv/preconfigure    | 13 +++++++++++--
 sysdeps/riscv/preconfigure.ac | 13 +++++++++++--
 2 files changed, 22 insertions(+), 4 deletions(-)
 mode change 100644 => 100755 sysdeps/riscv/preconfigure

diff --git a/sysdeps/riscv/preconfigure b/sysdeps/riscv/preconfigure
old mode 100644
new mode 100755
index 92ffa1ac02..57fe6822cf
--- a/sysdeps/riscv/preconfigure
+++ b/sysdeps/riscv/preconfigure
@@ -57,8 +57,17 @@ riscv*)
     esac
 
     if test -n "$vector"; then
-	version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __GNUC__ \(.*\)/\1/p'`
-	test $version -lt 15 && as_fn_error 1 "glibc requires GCC 15 or later for the V extension" "$LINENO" 5
+    	is_clang=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | grep -q '__clang__' && echo yes || echo no`
+	if test "$is_clang" = "yes"; then
+	    # Check clang version
+	    version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __clang_major__ \(.*\)/\1/p'`
+	    test $version -lt 21 && as_fn_error 1 "glibc requires Clang 21 or later for the V extension" "$LINENO" 5
+	else
+	    # Check GCC version
+	    version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __GNUC__ \(.*\)/\1/p'`
+	    test $version -lt 15 && as_fn_error 1 "glibc requires GCC 15 or later for the V extension" "$LINENO" 5
+	fi
+
 	test $vector -lt "1000000" && as_fn_error 1 "glibc requires at least RVV 1.0 for the V extension" "$LINENO" 5
 	float_machine=rvv
     fi
diff --git a/sysdeps/riscv/preconfigure.ac b/sysdeps/riscv/preconfigure.ac
index 99fbb0c9c9..52414919ae 100644
--- a/sysdeps/riscv/preconfigure.ac
+++ b/sysdeps/riscv/preconfigure.ac
@@ -57,8 +57,17 @@ riscv*)
     esac
 
     if test -n "$vector"; then
-	version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __GNUC__ \(.*\)/\1/p'`
-	test $version -lt 15 && AC_MSG_ERROR([glibc requires GCC 15 or later for the V extension], [1])
+    	is_clang=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | grep -q '__clang__' && echo yes || echo no`
+	if test "$is_clang" = "yes"; then
+	    # Check clang version
+	    version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __clang_major__ \(.*\)/\1/p'`
+	    test $version -lt 21 && AC_MSG_ERROR([glibc requires Clang 21 or later for the V extension], [1])
+	else
+	    # Check GCC version
+	    version=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null | sed -n 's/^#define __GNUC__ \(.*\)/\1/p'`
+	    test $version -lt 15 && AC_MSG_ERROR([glibc requires GCC 15 or later for the V extension], [1])
+	fi
+
 	test $vector -lt "1000000" && AC_MSG_ERROR([glibc requires at least RVV 1.0 for the V extension], [1])
 	float_machine=rvv
     fi
-- 
2.47.3