gnu: pcre@2: Fix run-time crash [security fix].

* gnu/packages/pcre.scm (pcre2)[replacement]: New field.
(pcre2/fixed): New public variable.
* packages/patches/pcre2-fix-jit_match-crash.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.

gnu/local.mk

@@ -1165,6 +1165,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/patchelf-rework-for-arm.patch		\
   %D%/packages/patches/patchutils-test-perms.patch		\
   %D%/packages/patches/patch-hurd-path-max.patch		\
+  %D%/packages/patches/pcre2-fix-jit_match-crash.patch		\
   %D%/packages/patches/perl-autosplit-default-time.patch	\
   %D%/packages/patches/perl-deterministic-ordering.patch	\
   %D%/packages/patches/perl-finance-quote-unuse-mozilla-ca.patch \

gnu/packages/pcre.scm

@@ -89,6 +89,7 @@ POSIX regular expression API.")
 (define-public pcre2
   (package
     (name "pcre2")
+    (replacement pcre2/fixed)
     (version "10.33")
     (source (origin
               (method url-fetch)
@@ -125,3 +126,14 @@ own native API, as well as a set of wrapper functions that correspond to the
 POSIX regular expression API.")
    (license license:bsd-3)
    (home-page "https://www.pcre.org/")))
+
+(define-public pcre2/fixed
+  ;; PHP >= 7.3.8 requires a fixed version at build time, so make it public
+  ;; and hide it in the UI.
+  (package
+    (inherit pcre2)
+    (source
+     (origin
+       (inherit (package-source pcre2))
+       (patches (search-patches "pcre2-fix-jit_match-crash.patch"))))
+    (properties '((hidden? . #t)))))