Add sample meta patch

10 files changed, 1167 insertions, 23 deletions

diff --git a/.reuse/dep5 b/.reuse/dep5
index 63ea501..5aa58da 100644
--- a/.reuse/dep5
+++ b/.reuse/dep5
@@ -3,14 +3,34 @@ Source: https://trong.loang.org/~cnx/bux
 Upstream-Name: bux
 Upstream-Contact: Nguyễn Gia Phong <cnx@loang.net>
 
+Files: grep/8f08d8e2.meta.patch
+Copyright: 2010 Free Software Foundation
+License: GPL-3.0-or-later
+
+Files: md4c/36.md
+Copyright: 2018 Martin Mitáš
+License: MIT
+
+Files: md4c/bf022cb65694.meta.patch
+Copyright: 2018 Martin Mitáš
+License: MIT
+
 Files: md4c/107.md
 Copyright: 2020 Martin Mitáš
 License: MIT
 
+Files: md4c/5d7c35973e5d.meta.patch
+Copyright: 2020 Martin Mitáš
+License: MIT
+
 Files: md4c/fix-pkgconfig.patch
 Copyright: 2023 Nguyễn Gia Phong
 License: AGPL-3.0-or-later
 
+Files: md4c/install.patch
+Copyright: 2019 Lisandro Damián Nicanor Pérez Meyer
+License: MIT
+
 Files: README.md
 Copyright: N/A
 License: CC0-1.0
diff --git a/LICENSES/GPL-3.0-or-later.txt b/LICENSES/GPL-3.0-or-later.txt
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSES/GPL-3.0-or-later.txt
@@ -0,0 +1,674 @@
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+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
diff --git a/grep/8f08d8e2.meta.patch b/grep/8f08d8e2.meta.patch
new file mode 100644
index 0000000..91eabd8
--- /dev/null
+++ b/grep/8f08d8e2.meta.patch
@@ -0,0 +1,116 @@
+diff --git a/NEWS b/NEWS
+index ba021869b184..a9acb822e95d 100644
+--- a/NEWS
++++ b/NEWS
+@@ -10,6 +10,9 @@ GNU grep NEWS                                    -*- outline -*-
+   Character ranges would not work in single-byte character sets other
+   than C (for example, ISO-8859-1 or KOI8-R).  [bug introduced in 2.6]
+ 
++  The output of grep was incorrect for whole-word (-w) matches if the
++  patterns included a backreference.
++
+ ** Portability
+ 
+   Avoid a link failure on Solaris 8.
+diff --git a/src/dfasearch.c b/src/dfasearch.c
+index a43f822aafa0..2dbe6b11bcc4 100644
+--- a/src/dfasearch.c
++++ b/src/dfasearch.c
+@@ -18,6 +18,57 @@
+ 
+ /* Written August 1992 by Mike Haertel. */
+ 
++#include <stdbool.h>
++#include <stdint.h>
++#include <stdlib.h>
++
++void klee_assume(uintptr_t x) {}
++void klee_mark_patch(uint64_t patch_num) {}
++
++bool __klee_runtime = true;
++void
++klee_make_symbolic(void *addr, size_t nbytes, const char *name)
++{
++  __klee_runtime = false;
++}
++
++int
++__choose(const char *switch_id)
++{
++  char *env = getenv(switch_id);
++  if (env == NULL)
++    return 0;
++  int result=atoi(env);
++  return result;
++}
++
++#define MAX_NAME_LENGTH 1000
++#define SYMBOLIC_OUTPUT_PROTO(type, typestr)        \
++type                                                \
++angelix_symbolic_output_##type(type expr, char* id) \
++{                                                   \
++  if (!__klee_runtime)                              \
++    return expr;                                    \
++  static int instance = 0;                          \
++  char name[MAX_NAME_LENGTH];                       \
++  sprintf(name, "out!%s!%d", id, instance++);       \
++  type s;                                           \
++  klee_make_symbolic(&s, sizeof(s), name);          \
++  klee_assume(s == expr);                           \
++  return s;                                         \
++}
++SYMBOLIC_OUTPUT_PROTO(int, "int")
++SYMBOLIC_OUTPUT_PROTO(long, "long")
++SYMBOLIC_OUTPUT_PROTO(size_t, "size_t")
++SYMBOLIC_OUTPUT_PROTO(bool, "bool")
++SYMBOLIC_OUTPUT_PROTO(char, "char")
++#undef SYMBOLIC_OUTPUT_PROTO
++
++#define ANGELIX_OUTPUT(type, expr, name) \
++  angelix_symbolic_output_##type((expr), (name))
++
++#define __COMPILE_40
++
+ #include <config.h>
+ #include "search.h"
+ #include "dfa.h"
+@@ -357,8 +408,20 @@ EGexecute (char const *buf, size_t size, size_t *match_size,
+ 		{
+ 		  /* Good enough for a non-exact match.
+ 		     No need to look at further patterns, if any.  */
++char __choose2 = __choose("__SWITCH2");
++klee_make_symbolic(&__choose2, sizeof(__choose2), "__choose2");
++if (__choose2 == 0)
++  {
+ 		  beg = match;
+ 		  goto success_in_len;
++  }
++#ifdef __COMPILE_40
++else if (__choose2 == 3)
++  {
++		  klee_mark_patch(40);
++		  goto success;
++  }
++#endif
+ 		}
+ 	      if (match < best_match || (match == best_match && len > best_len))
+ 		{
+@@ -388,5 +451,6 @@ EGexecute (char const *buf, size_t size, size_t *match_size,
+   *match_size = len;
+   ret_val = beg - buf;
+  out:
++  ANGELIX_OUTPUT(size_t, *match_size, "match_size");
+   return ret_val;
+ }
+diff --git a/tests/Makefile.am b/tests/Makefile.am
+index 02db64c44ab3..59ed67223445 100644
+--- a/tests/Makefile.am
++++ b/tests/Makefile.am
+@@ -16,6 +16,7 @@
+ 
+ TESTS =						\
+   backref.sh					\
++  backref-word					\
+   bre.sh					\
+   case-fold-backref				\
+   case-fold-backslash-w				\
diff --git a/grep/default.nix b/grep/default.nix
index 5585c10..6e3293e 100644
--- a/grep/default.nix
+++ b/grep/default.nix
@@ -9,7 +9,7 @@
 # SPDX-FileCopyrightText: 2023 Nguyễn Gia Phong
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
-{ lib, stdenv, version, base, snapshot
+{ lib, stdenv, version, base, snapshot, patches
 , bcExtractHook, binRenameHook, pcre, libiconv }:
 stdenv.mkDerivation rec {
   pname = "grep";
@@ -20,7 +20,8 @@ stdenv.mkDerivation rec {
   hardeningDisable = [ "all" ];
 
   src = base;  # bootstrap files
-  postPatch = ''
+  inherit patches;
+  prePatch = ''
     tar xf ${snapshot} --strip-components=1
   '';
 
diff --git a/md4c/36.md b/md4c/36.md
new file mode 100644
index 0000000..9f7fa12
--- /dev/null
+++ b/md4c/36.md
@@ -0,0 +1 @@
+__x_ _x___
diff --git a/md4c/5d7c35973e5d.meta.patch b/md4c/5d7c35973e5d.meta.patch
new file mode 100644
index 0000000..4bc8205
--- /dev/null
+++ b/md4c/5d7c35973e5d.meta.patch
@@ -0,0 +1,79 @@
+diff --git a/md4c/md4c.c b/md4c/md4c.c
+index a71ba3655909..d95fd7d5b7b7 100644
+--- a/md4c/md4c.c
++++ b/md4c/md4c.c
+@@ -29,7 +29,55 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
++#include <stdbool.h>
++#include <stdint.h>
+ 
++void klee_assume(uintptr_t x) {}
++void klee_mark_patch(uint64_t patch_num) {}
++
++bool __klee_runtime = true;
++void
++klee_make_symbolic(void *addr, size_t nbytes, const char *name)
++{
++  __klee_runtime = false;
++}
++
++int
++__choose(const char *switch_id)
++{
++  char *env = getenv(switch_id);
++  if (env == NULL)
++    return 0;
++  int result=atoi(env);
++  return result;
++}
++
++#define MAX_NAME_LENGTH 1000
++#define SYMBOLIC_OUTPUT_PROTO(type, typestr)        \
++type                                                \
++angelix_symbolic_output_##type(type expr, char* id) \
++{                                                   \
++  if (!__klee_runtime)                              \
++    return expr;                                    \
++  static int instance = 0;                          \
++  char name[MAX_NAME_LENGTH];                       \
++  sprintf(name, "out!%s!%d", id, instance++);       \
++  type s;                                           \
++  klee_make_symbolic(&s, sizeof(s), name);          \
++  klee_assume(s == expr);                           \
++  return s;                                         \
++}
++SYMBOLIC_OUTPUT_PROTO(int, "int")
++SYMBOLIC_OUTPUT_PROTO(long, "long")
++SYMBOLIC_OUTPUT_PROTO(size_t, "size_t")
++SYMBOLIC_OUTPUT_PROTO(bool, "bool")
++SYMBOLIC_OUTPUT_PROTO(char, "char")
++#undef SYMBOLIC_OUTPUT_PROTO
++
++#define ANGELIX_OUTPUT(type, expr, name) \
++  angelix_symbolic_output_##type((expr), (name))
++
++#define __COMPILE_42
+ 
+ /*****************************
+  ***  Miscellaneous Stuff  ***
+@@ -3726,7 +3774,17 @@ md_analyze_emph(MD_CTX* ctx, int mark_index)
+         if(opener != NULL) {
+             SZ opener_size = opener->end - opener->beg;
+             SZ closer_size = mark->end - mark->beg;
+-            MD_MARKCHAIN* opener_chain = md_mark_chain(ctx, mark_index);
++            MD_MARKCHAIN* opener_chain;
++char __choose2 = __choose("__SWITCH2");
++klee_make_symbolic(&__choose2, sizeof(__choose2), "__choose2");
++if (__choose2 == 0) {
++            opener_chain = md_mark_chain(ctx, mark_index);
++}
++#ifdef __COMPILE_42
++else if (__choose2 == 3) {
++            opener_chain = md_mark_chain(ctx, opener_index);
++}
++#endif
+ 
+             if(opener_size > closer_size) {
+                 opener_index = md_split_emph_mark(ctx, opener_index, closer_size);
diff --git a/md4c/bf022cb65694.meta.patch b/md4c/bf022cb65694.meta.patch
new file mode 100644
index 0000000..e9f9f92
--- /dev/null
+++ b/md4c/bf022cb65694.meta.patch
@@ -0,0 +1,79 @@
+diff --git a/md4c/md4c.c b/md4c/md4c.c
+index e6b2b94a4b97..ad14e413fe94 100644
+--- a/md4c/md4c.c
++++ b/md4c/md4c.c
+@@ -28,6 +28,55 @@
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
++#include <stdbool.h>
++#include <stdint.h>
++
++void klee_assume(uintptr_t x) {}
++void klee_mark_patch(uint64_t patch_num) {}
++
++bool __klee_runtime = true;
++void
++klee_make_symbolic(void *addr, size_t nbytes, const char *name)
++{
++  __klee_runtime = false;
++}
++
++int
++__choose(const char *switch_id)
++{
++  char *env = getenv(switch_id);
++  if (env == NULL)
++    return 0;
++  int result=atoi(env);
++  return result;
++}
++
++#define MAX_NAME_LENGTH 1000
++#define SYMBOLIC_OUTPUT_PROTO(type, typestr)        \
++type                                                \
++angelix_symbolic_output_##type(type expr, char* id) \
++{                                                   \
++  if (!__klee_runtime)                              \
++    return expr;                                    \
++  static int instance = 0;                          \
++  char name[MAX_NAME_LENGTH];                       \
++  sprintf(name, "out!%s!%d", id, instance++);       \
++  type s;                                           \
++  klee_make_symbolic(&s, sizeof(s), name);          \
++  klee_assume(s == expr);                           \
++  return s;                                         \
++}
++SYMBOLIC_OUTPUT_PROTO(int, "int")
++SYMBOLIC_OUTPUT_PROTO(long, "long")
++SYMBOLIC_OUTPUT_PROTO(size_t, "size_t")
++SYMBOLIC_OUTPUT_PROTO(bool, "bool")
++SYMBOLIC_OUTPUT_PROTO(char, "char")
++#undef SYMBOLIC_OUTPUT_PROTO
++
++#define ANGELIX_OUTPUT(type, expr, name) \
++  angelix_symbolic_output_##type((expr), (name))
++
++#define __COMPILE_42
+ 
+ 
+ /*****************************
+@@ -3490,7 +3539,17 @@ static int
+ md_split_simple_pairing_mark(MD_CTX* ctx, int mark_index, SZ n)
+ {
+     MD_MARK* mark = &ctx->marks[mark_index];
+-    int new_mark_index = mark_index + (mark->end - mark->beg - 1);
++    int new_mark_index;
++char __choose2 = __choose("__SWITCH2");
++klee_make_symbolic(&__choose2, sizeof(__choose2), "__choose2");
++if (__choose2 == 0) {
++    new_mark_index = mark_index + (mark->end - mark->beg - 1);
++}
++#ifdef __COMPILE_42
++else if (__choose2 == 3) {
++    new_mark_index = mark_index + (mark->end - mark->beg - n);
++}
++#endif
+     MD_MARK* dummy = &ctx->marks[new_mark_index];
+ 
+     MD_ASSERT(mark->end - mark->beg > n);
diff --git a/md4c/default.nix b/md4c/default.nix
index aa51e1d..a918e7d 100644
--- a/md4c/default.nix
+++ b/md4c/default.nix
@@ -8,27 +8,30 @@
 # SPDX-FileCopyrightText: 2023 Nguyễn Gia Phong
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
-{ lib, stdenv, version, fetchFromGitHub, commit, hash
+{ lib, stdenv, version, fetchFromGitHub, commit, hash, patches
 , bcExtractHook, binRenameHook, cmake, pkg-config }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation {
   pname = "md4c";
   inherit version;
 
   src = fetchFromGitHub {
     owner = "mity";
-    repo = pname;
+    repo = "md4c";
     rev = commit;
     inherit hash;
   };
 
-  patches = [
+  patches = patches ++ [
     # We set CMAKE_INSTALL_LIBDIR to the absolute path in $out, so
     # prefix and exec_prefix cannot be $out, too
     # Use CMake's _FULL_ variables instead of `prefix` concatenation.
     ./fix-pkgconfig.patch
   ];
 
+  # RPATH of binary [...] contains a forbidden reference to /build/
+  cmakeFlags = [ "-DCMAKE_SKIP_BUILD_RPATH=ON" ];
+
   nativeBuildInputs = [ bcExtractHook binRenameHook cmake pkg-config ];
 
   meta = with lib; {
diff --git a/md4c/install.patch b/md4c/install.patch
new file mode 100644
index 0000000..1d58f2c
--- /dev/null
+++ b/md4c/install.patch
@@ -0,0 +1,172 @@
+From 188ab6d9f617bec313e561e0f238b57447b113a1 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Lisandro=20Dami=C3=A1n=20Nicanor=20P=C3=A9rez=20Meyer?=
+ <perezmeyer@gmail.com>
+Date: Thu, 7 Feb 2019 15:54:25 -0300
+Subject: [PATCH] Build md4c as a shared library. (#49)
+
+Build md4c as a shared library.
+
+- Define the current version in the main CMakeLists.txt, so it can be used
+  within the project.
+- Define VERSION, SOVERSION and PUBLIC_HEADER as target properties.
+- Be able to install both libmd4c and md2html.
+- Create a pkg-config file.
+
+Fixes #48
+---
+ CMakeLists.txt         | 13 ++++++++++++-
+ README.md              |  4 ++++
+ appveyor.yml           |  2 +-
+ md2html/CMakeLists.txt |  2 ++
+ md4c/CMakeLists.txt    | 29 ++++++++++++++++++++++++++++-
+ md4c/md4c.h            |  6 ------
+ md4c/md4c.pc.in        | 12 ++++++++++++
+ 7 files changed, 59 insertions(+), 9 deletions(-)
+ create mode 100644 md4c/md4c.pc.in
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index a32d7d8effc1..d4eeec5ad195 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -1,7 +1,17 @@
+ 
+-cmake_minimum_required(VERSION 2.8)
++cmake_minimum_required(VERSION 3.4)
+ project(MD4C C)
+ 
++set(MD_VERSION_MAJOR 0)
++set(MD_VERSION_MINOR 2)
++set(MD_VERSION_RELEASE 7)
++set(MD_VERSION "${MD_VERSION_MAJOR}.${MD_VERSION_MINOR}.${MD_VERSION_RELEASE}")
++
++add_definitions(
++    -DMD_VERSION_MAJOR=${MD_VERSION_MAJOR}
++    -DMD_VERSION_MINOR=${MD_VERSION_MINOR}
++    -DMD_VERSION_RELEASE=${MD_VERSION_RELEASE}
++)
+ 
+ set(CMAKE_CONFIGURATION_TYPES Debug Release RelWithDebInfo MinSizeRel)
+ if("${CMAKE_BUILD_TYPE}" STREQUAL "")
+@@ -26,6 +36,7 @@ elseif(MSVC)
+     set(CMAKE_C_FLAGS_MINSIZEREL "${CMAKE_C_FLAGS_RELEASE} /MT")
+ endif()
+ 
++include(GNUInstallDirs)
+ 
+ add_subdirectory(md4c)
+ add_subdirectory(md2html)
+diff --git a/README.md b/README.md
+index 6a77a338c958..b393b0ca5c9c 100644
+--- a/README.md
++++ b/README.md
+@@ -55,6 +55,10 @@ MD4C is C Markdown parser with the following features:
+   [Cmark](https://github.com/jgm/cmark).
+ 
+ 
++## Building MD4C as a shared library
++
++Be sure to define BUILD_SHARED_LIBS when building.
++
+ ## Using MD4C
+ 
+ The parser is implemented in a single C source file `md4c.c` and its
+diff --git a/appveyor.yml b/appveyor.yml
+index 995a51dda515..a254b4f2069e 100644
+--- a/appveyor.yml
++++ b/appveyor.yml
+@@ -10,7 +10,7 @@ before_build:
+ 
+ build:
+   project: md4c.sln
+-  verbosity: minimal
++  verbosity: detailed
+ 
+ skip_tags: true
+ 
+diff --git a/md2html/CMakeLists.txt b/md2html/CMakeLists.txt
+index a8733125d020..b7bdee2d2874 100644
+--- a/md2html/CMakeLists.txt
++++ b/md2html/CMakeLists.txt
+@@ -3,3 +3,5 @@ include_directories("${PROJECT_SOURCE_DIR}/md4c")
+ 
+ add_executable(md2html cmdline.c cmdline.h entity.c entity.h md2html.c render_html.c render_html.h)
+ target_link_libraries(md2html md4c)
++
++install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/md2html DESTINATION ${CMAKE_INSTALL_BINDIR})
+diff --git a/md4c/CMakeLists.txt b/md4c/CMakeLists.txt
+index f9577a31e9ef..8fc846ff5623 100644
+--- a/md4c/CMakeLists.txt
++++ b/md4c/CMakeLists.txt
+@@ -1,6 +1,33 @@
++# Be sure to export all symbols in Windows.
++set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS 1)
+ 
+ set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -DDEBUG")
+ 
+ add_definitions(-DMD4C_USE_UTF8)
+ 
+-add_library(md4c STATIC md4c.c md4c.h)
++set(md4c_src
++    md4c.c
++)
++
++add_library(md4c SHARED ${md4c_src})
++
++set_target_properties(md4c PROPERTIES
++    VERSION ${MD_VERSION}
++    SOVERSION ${MD_VERSION_MAJOR}
++    PUBLIC_HEADER md4c.h
++)
++
++install(
++    TARGETS md4c
++    EXPORT md4cConfig
++    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
++    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
++    PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
++)
++
++# Create a pkg-config file
++configure_file(md4c.pc.in md4c.pc @ONLY)
++install(FILES ${CMAKE_BINARY_DIR}/md4c/md4c.pc DESTINATION ${CMAKE_INSTALL_DATAROOTDIR}/pkgconfig)
++
++# And a CMake file
++install(EXPORT md4cConfig DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/md4c/)
+diff --git a/md4c/md4c.h b/md4c/md4c.h
+index c68527bedcad..226f3bd2748b 100644
+--- a/md4c/md4c.h
++++ b/md4c/md4c.h
+@@ -30,12 +30,6 @@
+     extern "C" {
+ #endif
+ 
+-
+-#define MD_VERSION_MAJOR        0
+-#define MD_VERSION_MINOR        2
+-#define MD_VERSION_RELEASE      3
+-
+-
+ /* Magic to support UTF-16. */
+ #if defined MD4C_USE_UTF16
+     #ifdef _WIN32
+diff --git a/md4c/md4c.pc.in b/md4c/md4c.pc.in
+new file mode 100644
+index 000000000000..61c78d890249
+--- /dev/null
++++ b/md4c/md4c.pc.in
+@@ -0,0 +1,12 @@
++prefix=@CMAKE_INSTALL_PREFIX@
++exec_prefix=@CMAKE_INSTALL_PREFIX@
++libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
++includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
++
++Name: @PROJECT_NAME@
++Description: @PROJECT_DESCRIPTION@
++Version: @PROJECT_VERSION@
++
++Requires:
++Libs: -L${libdir} -lmd4c
++Cflags: -I${includedir}
+-- 
+2.41.0
+
diff --git a/shell.nix b/shell.nix
index 85ce48e..840402b 100644
--- a/shell.nix
+++ b/shell.nix
@@ -55,7 +55,7 @@ let
     url = "mirror://gnu/grep/grep-2.12.tar.xz";
     hash = "sha256-Tc4KT7g93QEg31HgC1L6dg8u2GddTUwLCuZCumkurWQ=";
   };
-  grep = version: base: commit: hash: callPackage ./grep {
+  grep = version: base: commit: hash: patches: callPackage ./grep {
     stdenv = wllvmStdenv;
     inherit version;
     inherit base;
@@ -63,14 +63,16 @@ let
       url = "http://git.savannah.gnu.org/cgit/grep.git/snapshot/grep-${commit}.tar.gz";
       inherit hash;
     };
+    inherit patches;
     inherit bcExtractHook;
     binRenameHook = binRenameHook version;
   };
-  md4c = version: commit: hash: callPackage ./md4c {
+  md4c = version: commit: hash: patches: callPackage ./md4c {
     stdenv = wllvmStdenv;
     inherit version;
     inherit commit;
     inherit hash;
+    inherit patches;
     inherit bcExtractHook;
     binRenameHook = binRenameHook version;
   };
@@ -105,24 +107,21 @@ in mkShell {
     (cppcheck "9261.fixed"
       "00fae7fb428b0b055135d6b972a1b52dd2c08d03"
       "sha256-jJY06u07fzd9AOd1pr7xM7Qdm6oDW1ehGEqKlxxHT6s=")
-    (grep "8f08d8e2.parent" grep-2_6
+    (grep "8f08d8e2.meta" grep-2_6
       "c1cb19fe67f4c83f9232087ae03c178905d62b0d"
-      "sha256-tT3H9pehJ8X6XPf6qyhUvjKspQZXvCd2I4uQQuabOn8=")
-    (grep "8f08d8e2" grep-2_6
-      "8f08d8e282bf3d4917e94135e67ba17d738313ce"
-      "sha256-xQO/d/nTk/q/7Sq6m+exZX7jwYzqbhcKirw9tqC7+zI=")
+      "sha256-tT3H9pehJ8X6XPf6qyhUvjKspQZXvCd2I4uQQuabOn8="
+      [ grep/8f08d8e2.meta.patch ])
     (grep "55cf7b6a.parent" grep-2_12
       "a2e0193455e620f6bad1005500da418d9eba2ae6"
-      "sha256-Q1Xye4qHdWOlZSJ+S+T9Cy/71OLN+WE97Va84BFoV/Q=")
-    (grep "55cf7b6a" grep-2_12
-      "55cf7b6a1905320c36702a476b09ebb29a2934d3"
-      "sha256-uUHEG4bDDNFiVgj/1mIkttp1B7tlZ1HOWJGPEfbCErU=")
-    (md4c "107.buggy"
+      "sha256-Q1Xye4qHdWOlZSJ+S+T9Cy/71OLN+WE97Va84BFoV/Q="
+      [ ])
+    (md4c "36.meta"
+      "e7b84d65a42048f812a006e88ca1b353d7828974"
+      "sha256-mJdL0p15PnmBd16wyjM0Utd/rowek2FdeoBMG/wkATk="
+      [ md4c/install.patch md4c/bf022cb65694.meta.patch ])
+    (md4c "107.meta"
       "e278609ee06ad7f9efcb06da48188a4b837ed11b"
-      "sha256-UoqBSOnlfDsTHz/uLGIUEgmTSiU408iUcwAJTLdbEPM=")
-    (md4c "107.fixed"
-      "5d7c35973e5d06b46ca21b5b6e292c56dba7ca23"
-      "sha256-N/vIRhXuU948z0O4NXKMSKOZGAEE6UjGDT5oqrGpUy8=")
-    klee
+      "sha256-UoqBSOnlfDsTHz/uLGIUEgmTSiU408iUcwAJTLdbEPM="
+      [ md4c/5d7c35973e5d.meta.patch ])
   ];
 }