Update release notes about regex changes

diff --git a/doc/release-notes/release-4.sgml b/doc/release-notes/release-4.sgml
index 47dbe9803a6a23358f2bcd0c1d2b2c891ecf4031..a730d1ed979c85e3fa9cdf499dd1657bbf48af24 100644 (file)
--- a/doc/release-notes/release-4.sgml
+++ b/doc/release-notes/release-4.sgml
@@ -120,8 +120,9 @@ This section gives a thorough account of those changes in three categories:
 <descrip>
        <tag>acl</tag>
        <p>Due to differences between GNU Regex and libc regular expressions
-          patterns using the double quote (") character may now be rejected
-          by *_regex and regular expression based ACL types.
+          patterns escaping the double quote (") character escaped by a slash (\)
+          will now be rejected. Use without the escaping is still accepted.
+          This affects all *_regex and regular expression based ACL types.
 
        <tag>auth_param</tag>
        <p>New parameter <em>queue-size=</em> to set the maximum number
@@ -163,8 +164,9 @@ This section gives a thorough account of those changes in three categories:
           performed by default with correct HTTP/1.1 revalidation.
        <p>Removed <em>ignore-must-revalidate</em>. Other more HTTP compliant
           directives can be used to prevent objects from caching.
-       <p>Due to differences between GNURegex and libc regular expressions
-          patterns using the double quote (") character may now be rejected.
+       <p>Due to differences between GNU Regex and libc regular expressions
+          patterns escaping the double quote (") character with a slash (\)
+          will now be rejected. Use without the escaping is still accepted.
 
        <tag>sslcrtd_children</tag>
        <p>New parameter <em>queue-size=</em> to set the maximum number
@@ -257,6 +259,17 @@ This section gives an account of those changes in three categories:
        <tag>--enable-gnuregex</tag>
        <p>Squid now uses C++11 std::regex instead of GNU Regex. Removed.
 
+       <tag>LDFLAGS</tag>
+       <p>Squid now uses C++11 std::regex API instead of the C regex.h API.
+          This means that linker overrides for -lregex and regex.h no longer exist.
+       <p>Custom regex libraries need to provide bindings for the std::regex
+          API to link with Squid. This may require additional -I path to be
+          provided in CXXFLAGS to the library headers. Refer to the chosen
+          library documentation for more details.
+       <p>Note that popular modern high performance regex libraries should
+          already be used by the STL internal implementation and no longer
+          need manually linking.
+
 </descrip>