From e36cba8a36c52246fc4e6132338eb0b087daa888 Mon Sep 17 00:00:00 2001
From: Kyle Evans <kevans@FreeBSD.org>
Date: Mon, 22 Jan 2018 18:40:19 +0000
Subject: [PATCH] libregex: Add a symbol map

kib points out that trying to re-use symbol versioning from libc is dirty
and wrong. The implementation in libregex is incompatible by design with the
implementation in libc. Using the symbol versions from libc can and likely
will cause confusions for linkers and bring unexpected behavior for
consumers that unwillingly (transitively) link against libregex.

Reported by:	kib
---
 lib/libregex/Makefile     |  4 +++-
 lib/libregex/Symbol.map   | 16 ++++++++++++++++
 lib/libregex/Versions.def |  5 +++++
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 lib/libregex/Symbol.map
 create mode 100644 lib/libregex/Versions.def

diff --git a/lib/libregex/Makefile b/lib/libregex/Makefile
index eb6b0b64650..186bb20088c 100644
--- a/lib/libregex/Makefile
+++ b/lib/libregex/Makefile
@@ -9,9 +9,11 @@ SHLIB_MINOR=	0
 
 CFLAGS+=	-DLIBREGEX
 LIBC_SRCTOP=	${.CURDIR:H}/libc
-SYMBOL_MAPS=	${SYM_MAPS}
 WARNS?=	2
 
+VERSION_DEF=	${.CURDIR}/Versions.def
+SYMBOL_MAPS=	${.CURDIR}/Symbol.map
+
 #HAS_TESTS=
 SUBDIR.${MK_TESTS}+= tests
 
diff --git a/lib/libregex/Symbol.map b/lib/libregex/Symbol.map
new file mode 100644
index 00000000000..09cd2118372
--- /dev/null
+++ b/lib/libregex/Symbol.map
@@ -0,0 +1,16 @@
+/*
+ * $FreeBSD$
+ */
+
+/*
+ * libregex uses a different version name because its symbols are not strictly
+ * compatible with those provided by libc. Re-using the version name from libc
+ * could cause linking headaches and make debugging more difficult than it needs
+ * to be.
+ */
+LIBREGEX_1.0 {
+	regcomp;
+	regerror;
+	regexec;
+	regfree;
+};
diff --git a/lib/libregex/Versions.def b/lib/libregex/Versions.def
new file mode 100644
index 00000000000..b6c84200762
--- /dev/null
+++ b/lib/libregex/Versions.def
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+LIBREGEX_1.0 {
+};
+