From fae8d2627db00bd07d0a80669be26648161c86c0 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Mon, 4 Nov 2019 19:57:14 -0500
Subject: [PATCH 01/17] cc-wrapper, bintools-wrapper: Remove now unneeded `set
 {+,-}u`

---
 pkgs/build-support/bintools-wrapper/default.nix   | 6 +-----
 pkgs/build-support/bintools-wrapper/setup-hook.sh | 3 ---
 pkgs/build-support/cc-wrapper/default.nix         | 4 ----
 pkgs/build-support/cc-wrapper/setup-hook.sh       | 3 ---
 4 files changed, 1 insertion(+), 15 deletions(-)

diff --git a/pkgs/build-support/bintools-wrapper/default.nix b/pkgs/build-support/bintools-wrapper/default.nix
index 9f5395b635e0..4a56f00db49e 100644
--- a/pkgs/build-support/bintools-wrapper/default.nix
+++ b/pkgs/build-support/bintools-wrapper/default.nix
@@ -199,11 +199,7 @@ stdenv.mkDerivation {
   ];
 
   postFixup =
-    ''
-      set -u
-    ''
-
-    + optionalString (libc != null) (''
+    optionalString (libc != null) (''
       ##
       ## General libc support
       ##
diff --git a/pkgs/build-support/bintools-wrapper/setup-hook.sh b/pkgs/build-support/bintools-wrapper/setup-hook.sh
index 2e15fa95c794..a714bd151c90 100644
--- a/pkgs/build-support/bintools-wrapper/setup-hook.sh
+++ b/pkgs/build-support/bintools-wrapper/setup-hook.sh
@@ -2,8 +2,6 @@
 #
 # See comments in cc-wrapper's setup hook. This works exactly the same way.
 
-set -u
-
 # Skip setup hook if we're neither a build-time dep, nor, temporarily, doing a
 # native compile.
 #
@@ -73,4 +71,3 @@ export NIX_HARDENING_ENABLE
 
 # No local scope in sourced file
 unset -v role_pre role_post cmd upper_case
-set +u
diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index cf2d38cd9978..d6037552ef6e 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -134,8 +134,6 @@ stdenv.mkDerivation {
 
   installPhase =
     ''
-      set -u
-
       mkdir -p $out/bin $out/nix-support
 
       wrap() {
@@ -224,8 +222,6 @@ stdenv.mkDerivation {
 
   postFixup =
     ''
-      set -u
-
       # Backwards compatability for packages expecting this file, e.g. with
       # `$NIX_CC/nix-support/dynamic-linker`.
       #
diff --git a/pkgs/build-support/cc-wrapper/setup-hook.sh b/pkgs/build-support/cc-wrapper/setup-hook.sh
index 211b50632914..5b13f2683097 100644
--- a/pkgs/build-support/cc-wrapper/setup-hook.sh
+++ b/pkgs/build-support/cc-wrapper/setup-hook.sh
@@ -54,8 +54,6 @@
 # For more details, read the individual files where the mechanisms used to
 # accomplish this will be individually documented.
 
-set -u
-
 # Skip setup hook if we're neither a build-time dep, nor, temporarily, doing a
 # native compile.
 #
@@ -120,4 +118,3 @@ export NIX_HARDENING_ENABLE
 
 # No local scope in sourced file
 unset -v role_pre role_post
-set +u

From cdbbaa91edc3179abee15b4597b8710aa8d0ca87 Mon Sep 17 00:00:00 2001
From: John Ericson <git@JohnEricson.me>
Date: Tue, 5 Nov 2019 09:55:39 -0500
Subject: [PATCH 02/17] cmake: CMAKE_*_PATH can be undefined

---
 .../tools/build-managers/cmake/setup-hook.sh           | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/pkgs/development/tools/build-managers/cmake/setup-hook.sh b/pkgs/development/tools/build-managers/cmake/setup-hook.sh
index 8bd54d3bc13d..d5e88d773f67 100755
--- a/pkgs/development/tools/build-managers/cmake/setup-hook.sh
+++ b/pkgs/development/tools/build-managers/cmake/setup-hook.sh
@@ -128,22 +128,22 @@ makeCmakeFindLibs(){
   for flag in $NIX_CFLAGS_COMPILE $NIX_LDFLAGS; do
     if test -n "$isystem_seen" && test -d "$flag"; then
       isystem_seen=
-      export CMAKE_INCLUDE_PATH="$CMAKE_INCLUDE_PATH${CMAKE_INCLUDE_PATH:+:}${flag}"
+      export CMAKE_INCLUDE_PATH="${CMAKE_INCLUDE_PATH-}${CMAKE_INCLUDE_PATH:+:}${flag}"
     elif test -n "$iframework_seen" && test -d "$flag"; then
       iframework_seen=
-      export CMAKE_FRAMEWORK_PATH="$CMAKE_FRAMEWORK_PATH${CMAKE_FRAMEWORK_PATH:+:}${flag}"
+      export CMAKE_FRAMEWORK_PATH="${CMAKE_FRAMEWORK_PATH-}${CMAKE_FRAMEWORK_PATH:+:}${flag}"
     else
       isystem_seen=
       iframework_seen=
       case $flag in
         -I*)
-          export CMAKE_INCLUDE_PATH="$CMAKE_INCLUDE_PATH${CMAKE_INCLUDE_PATH:+:}${flag:2}"
+          export CMAKE_INCLUDE_PATH="${CMAKE_INCLUDE_PATH-}${CMAKE_INCLUDE_PATH:+:}${flag:2}"
           ;;
         -L*)
-          export CMAKE_LIBRARY_PATH="$CMAKE_LIBRARY_PATH${CMAKE_LIBRARY_PATH:+:}${flag:2}"
+          export CMAKE_LIBRARY_PATH="${CMAKE_LIBRARY_PATH-}${CMAKE_LIBRARY_PATH:+:}${flag:2}"
           ;;
         -F*)
-          export CMAKE_FRAMEWORK_PATH="$CMAKE_FRAMEWORK_PATH${CMAKE_FRAMEWORK_PATH:+:}${flag:2}"
+          export CMAKE_FRAMEWORK_PATH="${CMAKE_FRAMEWORK_PATH-}${CMAKE_FRAMEWORK_PATH:+:}${flag:2}"
           ;;
         -isystem)
           isystem_seen=1

From 2c1d9d8bc1222abe8e597277eb1c3f1af2ac4423 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 14:21:42 -0500
Subject: [PATCH 03/17] i-score: CMAKE_PREFIX_PATH can be undefined

---
 pkgs/applications/audio/i-score/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/applications/audio/i-score/default.nix b/pkgs/applications/audio/i-score/default.nix
index 2cc39e649434..f3928499413c 100644
--- a/pkgs/applications/audio/i-score/default.nix
+++ b/pkgs/applications/audio/i-score/default.nix
@@ -70,7 +70,7 @@ stdenv.mkDerivation rec {
   ];
 
   preConfigure = ''
-    export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH:$(echo "${jamomacore}/jamoma/share/cmake/Jamoma")"
+    export CMAKE_PREFIX_PATH="''${CMAKE_PREFIX_PATH-}:$(echo "${jamomacore}/jamoma/share/cmake/Jamoma")"
   '';
 
   postInstall = ''rm $out/bin/i-score.sh'';

From 770a4c7946a1c55bf6295a34a42e1c4b657d1088 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:11:37 -0500
Subject: [PATCH 04/17] glib: Fix setup hook

It was not robust against multiple matching directories, as the called
function takes exactly 3 arguments.
---
 pkgs/development/libraries/glib/setup-hook.sh | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/libraries/glib/setup-hook.sh b/pkgs/development/libraries/glib/setup-hook.sh
index a1cb1f40c58a..20714ea7ab87 100644
--- a/pkgs/development/libraries/glib/setup-hook.sh
+++ b/pkgs/development/libraries/glib/setup-hook.sh
@@ -1,9 +1,11 @@
 
 make_glib_find_gsettings_schemas() {
     # For packages that need gschemas of other packages (e.g. empathy)
-    if [ -d "$1"/share/gsettings-schemas/*/glib-2.0/schemas ]; then
-        addToSearchPath GSETTINGS_SCHEMAS_PATH "$1/share/gsettings-schemas/"*
-    fi
+    for maybe_dir in "$1"/share/gsettings-schemas/*/glib-2.0; do
+        if [[ -d "$maybe_dir/schemas" ]]; then
+            addToSearchPath GSETTINGS_SCHEMAS_PATH "$maybe_dir"
+        fi
+    done
 }
 addEnvHooks "$hostOffset" make_glib_find_gsettings_schemas
 

From 42ffaf5290ec7c896c73d160151526041165115b Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:16:36 -0500
Subject: [PATCH 05/17] cmake: NIX_CFLAGS_COMPILE NIX_LDFLAG could be undefined

---
 pkgs/development/tools/build-managers/cmake/setup-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/tools/build-managers/cmake/setup-hook.sh b/pkgs/development/tools/build-managers/cmake/setup-hook.sh
index d5e88d773f67..52b9c3ab5f55 100755
--- a/pkgs/development/tools/build-managers/cmake/setup-hook.sh
+++ b/pkgs/development/tools/build-managers/cmake/setup-hook.sh
@@ -125,7 +125,7 @@ addEnvHooks "$targetOffset" addCMakeParams
 makeCmakeFindLibs(){
   isystem_seen=
   iframework_seen=
-  for flag in $NIX_CFLAGS_COMPILE $NIX_LDFLAGS; do
+  for flag in ${NIX_CFLAGS_COMPILE-} ${NIX_LDFLAGS-}; do
     if test -n "$isystem_seen" && test -d "$flag"; then
       isystem_seen=
       export CMAKE_INCLUDE_PATH="${CMAKE_INCLUDE_PATH-}${CMAKE_INCLUDE_PATH:+:}${flag}"

From 9167482d1275f2b17416ffcb18873237739f68c2 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:19:14 -0500
Subject: [PATCH 06/17] opensp: `sgmlHookDone` can be undefined

---
 pkgs/tools/text/sgml/opensp/setup-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/tools/text/sgml/opensp/setup-hook.sh b/pkgs/tools/text/sgml/opensp/setup-hook.sh
index 753a3ea64287..5bace3c66889 100644
--- a/pkgs/tools/text/sgml/opensp/setup-hook.sh
+++ b/pkgs/tools/text/sgml/opensp/setup-hook.sh
@@ -6,7 +6,7 @@ addSGMLCatalogs () {
       fi
 }
 
-if test -z "$sgmlHookDone"; then
+if test -z "${sgmlHookDone-}"; then
     sgmlHookDone=1
 
     # Set http_proxy and ftp_proxy to a invalid host to prevent

From 67cc85ec679eb16dc38908dfe78218544e637ee8 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:43:24 -0500
Subject: [PATCH 07/17] OCaml findlib: OCAMLPATH could be undefined

---
 pkgs/development/tools/ocaml/findlib/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/tools/ocaml/findlib/default.nix b/pkgs/development/tools/ocaml/findlib/default.nix
index fb1eb4276d62..7d95963209a3 100644
--- a/pkgs/development/tools/ocaml/findlib/default.nix
+++ b/pkgs/development/tools/ocaml/findlib/default.nix
@@ -32,7 +32,7 @@ stdenv.mkDerivation rec {
   setupHook = writeText "setupHook.sh" ''
     addOCamlPath () {
         if test -d "''$1/lib/ocaml/${ocaml.version}/site-lib"; then
-            export OCAMLPATH="''${OCAMLPATH}''${OCAMLPATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/"
+            export OCAMLPATH="''${OCAMLPATH-}''${OCAMLPATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/"
         fi
         if test -d "''$1/lib/ocaml/${ocaml.version}/site-lib/stublibs"; then
             export CAML_LD_LIBRARY_PATH="''${CAML_LD_LIBRARY_PATH}''${CAML_LD_LIBRARY_PATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/stublibs"

From 0b90a7f67f4df722a5c29773fcf8376d631f1fc8 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:45:48 -0500
Subject: [PATCH 08/17] lispPackages.clwrapper: NIX_LISP_LD_LIBRARY_PATH might
 be undefined

---
 pkgs/development/lisp-modules/clwrapper/setup-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/lisp-modules/clwrapper/setup-hook.sh b/pkgs/development/lisp-modules/clwrapper/setup-hook.sh
index 8975ada53206..da2303a18bfb 100644
--- a/pkgs/development/lisp-modules/clwrapper/setup-hook.sh
+++ b/pkgs/development/lisp-modules/clwrapper/setup-hook.sh
@@ -27,7 +27,7 @@ setLisp () {
 
 collectNixLispLDLP () {
      if echo "$1/lib"/lib*.so* | grep . > /dev/null; then
-	 export NIX_LISP_LD_LIBRARY_PATH="$NIX_LISP_LD_LIBRARY_PATH${NIX_LISP_LD_LIBRARY_PATH:+:}$1/lib"
+	 export NIX_LISP_LD_LIBRARY_PATH="${NIX_LISP_LD_LIBRARY_PATH-}${NIX_LISP_LD_LIBRARY_PATH:+:}$1/lib"
      fi
 }
 

From aaf0fd2c445d9d3bd686702d4b644d24ed3b10f3 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Tue, 5 Nov 2019 19:50:42 -0500
Subject: [PATCH 09/17] lua-5 setup hook: LUA_PATH and LUA_CPATH can be
 undefined

---
 pkgs/development/interpreters/lua-5/setup-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/interpreters/lua-5/setup-hook.sh b/pkgs/development/interpreters/lua-5/setup-hook.sh
index f7e56b62ac90..1c445b82afde 100644
--- a/pkgs/development/interpreters/lua-5/setup-hook.sh
+++ b/pkgs/development/interpreters/lua-5/setup-hook.sh
@@ -20,7 +20,7 @@ addToLuaSearchPathWithCustomDelimiter() {
   if [[ ! -d "$topDir" ]]; then return; fi
 
   # export only if we haven't already got this dir in the search path
-  if [[ ${!varName} == *"$absPattern"* ]]; then return; fi
+  if [[ ${!varName-} == *"$absPattern"* ]]; then return; fi
 
   export "${varName}=${!varName:+${!varName};}${absPattern}"
 }

From b78e84097fab550f365d39ca715632c7b9abd379 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 15:05:23 -0500
Subject: [PATCH 10/17] gdk-pixbuf setup hook: GDK_PIXBUF_MODULE_FILE might not
 be defined

Also switch to [[ ... ]] because it is more robust w.r.t. empty
arguments.
---
 pkgs/development/libraries/gdk-pixbuf/setup-hook.sh | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/pkgs/development/libraries/gdk-pixbuf/setup-hook.sh b/pkgs/development/libraries/gdk-pixbuf/setup-hook.sh
index 5a7dcd792996..8b6c80867a03 100644
--- a/pkgs/development/libraries/gdk-pixbuf/setup-hook.sh
+++ b/pkgs/development/libraries/gdk-pixbuf/setup-hook.sh
@@ -2,9 +2,9 @@ findGdkPixbufLoaders() {
 
 	# choose the longest loaders.cache
 	local loadersCache="$1/lib/gdk-pixbuf-2.0/2.10.0/loaders.cache"
-	if [ -f "$loadersCache" ]; then
-		if [ -f "$GDK_PIXBUF_MODULE_FILE" ]; then
-			if [ $(cat "$loadersCache"|wc -l) -gt $(cat "$GDK_PIXBUF_MODULE_FILE"|wc -l) ]; then
+	if [[ -f "$loadersCache" ]]; then
+		if [[ -f "${GDK_PIXBUF_MODULE_FILE-}" ]]; then
+			if [[ "$(cat "$loadersCache" | wc -l)" > "$(cat "$GDK_PIXBUF_MODULE_FILE" | wc -l)" ]]; then
 				export GDK_PIXBUF_MODULE_FILE="$loadersCache"
 			fi
 		else

From beda0365a64f025c26212cb69ffbb09f3ef329fd Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 15:12:29 -0500
Subject: [PATCH 11/17] darwin private frameworks setup hook:
 NIX_CFLAGS_COMPILE may be undefined

---
 .../darwin/apple-sdk/private-frameworks-setup-hook.sh           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/os-specific/darwin/apple-sdk/private-frameworks-setup-hook.sh b/pkgs/os-specific/darwin/apple-sdk/private-frameworks-setup-hook.sh
index fbd977f8552d..a351c39de130 100644
--- a/pkgs/os-specific/darwin/apple-sdk/private-frameworks-setup-hook.sh
+++ b/pkgs/os-specific/darwin/apple-sdk/private-frameworks-setup-hook.sh
@@ -1,6 +1,6 @@
 addPrivateFrameworks() {
     flag="-F/System/Library/PrivateFrameworks"
-    if [[ "$NIX_CFLAGS_COMPILE" != *$flag* ]]; then
+    if [[ "${NIX_CFLAGS_COMPILE-}" != *$flag* ]]; then
         NIX_CFLAGS_COMPILE+=" $flag"
     fi
 }

From 12a85a7046503e6ff602663a1d054407a4e3f184 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 15:20:02 -0500
Subject: [PATCH 12/17] SDL, SDL2: SDL{,2}_PATH may be undefined

---
 pkgs/development/libraries/SDL/setup-hook.sh  | 2 +-
 pkgs/development/libraries/SDL2/setup-hook.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/development/libraries/SDL/setup-hook.sh b/pkgs/development/libraries/SDL/setup-hook.sh
index 20382f18f529..32a7d0d95548 100644
--- a/pkgs/development/libraries/SDL/setup-hook.sh
+++ b/pkgs/development/libraries/SDL/setup-hook.sh
@@ -1,6 +1,6 @@
 addSDLPath () {
   if [ -e "$1/include/SDL" ]; then
-    export SDL_PATH="$SDL_PATH $1/include/SDL"
+    export SDL_PATH="${SDL_PATH-}${SDL_PATH:+ }$1/include/SDL"
   fi
 }
 
diff --git a/pkgs/development/libraries/SDL2/setup-hook.sh b/pkgs/development/libraries/SDL2/setup-hook.sh
index 3acce9d473c5..0119926491af 100644
--- a/pkgs/development/libraries/SDL2/setup-hook.sh
+++ b/pkgs/development/libraries/SDL2/setup-hook.sh
@@ -1,6 +1,6 @@
 addSDL2Path () {
   if [ -e "$1/include/SDL2" ]; then
-    export SDL2_PATH="$SDL2_PATH $1/include/SDL2"
+    export SDL2_PATH="${SDL2_PATH-}${SDL2_PATH:+ }$1/include/SDL2"
   fi
 }
 

From 908b143e510a0d6275d1960334e488173241251c Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 16:31:55 -0500
Subject: [PATCH 13/17] gstreamer: GST_PLUGIN_SYSTEM_PATH.* may be undefined

---
 pkgs/development/libraries/gstreamer/core/setup-hook.sh         | 2 +-
 .../libraries/gstreamer/legacy/gstreamer/setup-hook.sh          | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/development/libraries/gstreamer/core/setup-hook.sh b/pkgs/development/libraries/gstreamer/core/setup-hook.sh
index b8c741af578f..026a4e5f55a0 100644
--- a/pkgs/development/libraries/gstreamer/core/setup-hook.sh
+++ b/pkgs/development/libraries/gstreamer/core/setup-hook.sh
@@ -1,7 +1,7 @@
 addGstreamer1LibPath () {
     if test -d "$1/lib/gstreamer-1.0"
     then
-        export GST_PLUGIN_SYSTEM_PATH_1_0="${GST_PLUGIN_SYSTEM_PATH_1_0}${GST_PLUGIN_SYSTEM_PATH_1_0:+:}$1/lib/gstreamer-1.0"
+        export GST_PLUGIN_SYSTEM_PATH_1_0="${GST_PLUGIN_SYSTEM_PATH_1_0-}${GST_PLUGIN_SYSTEM_PATH_1_0:+:}$1/lib/gstreamer-1.0"
     fi
 }
 
diff --git a/pkgs/development/libraries/gstreamer/legacy/gstreamer/setup-hook.sh b/pkgs/development/libraries/gstreamer/legacy/gstreamer/setup-hook.sh
index 65ce26112519..636e20b732b4 100644
--- a/pkgs/development/libraries/gstreamer/legacy/gstreamer/setup-hook.sh
+++ b/pkgs/development/libraries/gstreamer/legacy/gstreamer/setup-hook.sh
@@ -1,7 +1,7 @@
 addGstreamerLibPath () {
     if test -d "$1/lib/gstreamer-0.10"
     then
-        export GST_PLUGIN_SYSTEM_PATH="${GST_PLUGIN_SYSTEM_PATH}${GST_PLUGIN_SYSTEM_PATH:+:}$1/lib/gstreamer-0.10"
+        export GST_PLUGIN_SYSTEM_PATH="${GST_PLUGIN_SYSTEM_PATH-}${GST_PLUGIN_SYSTEM_PATH:+:}$1/lib/gstreamer-0.10"
     fi
 }
 

From 6fb526b32c86bb3e5fdf5694e23f2f53d7d892ce Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 17:12:25 -0500
Subject: [PATCH 14/17] findlib setup hook: `createFindlibDestdir` may not be
 defined

---
 pkgs/development/tools/ocaml/findlib/default.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/tools/ocaml/findlib/default.nix b/pkgs/development/tools/ocaml/findlib/default.nix
index 7d95963209a3..4398d8e41881 100644
--- a/pkgs/development/tools/ocaml/findlib/default.nix
+++ b/pkgs/development/tools/ocaml/findlib/default.nix
@@ -38,7 +38,7 @@ stdenv.mkDerivation rec {
             export CAML_LD_LIBRARY_PATH="''${CAML_LD_LIBRARY_PATH}''${CAML_LD_LIBRARY_PATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/stublibs"
         fi
         export OCAMLFIND_DESTDIR="''$out/lib/ocaml/${ocaml.version}/site-lib/"
-        if test -n "$createFindlibDestdir"; then
+        if test -n "''${createFindlibDestdir-}"; then
           mkdir -p $OCAMLFIND_DESTDIR
         fi
     }

From f1481f2c9084d61cb5ebc55d4fa7edbc756128d3 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 17:17:41 -0500
Subject: [PATCH 15/17] apple-sdk setup hooks: NIX_CFLAGS_COMPILE may be
 undefined

---
 pkgs/os-specific/darwin/apple-sdk/cf-setup-hook.sh       | 2 +-
 pkgs/os-specific/darwin/apple-sdk/security-setup-hook.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/os-specific/darwin/apple-sdk/cf-setup-hook.sh b/pkgs/os-specific/darwin/apple-sdk/cf-setup-hook.sh
index 66e24fe58770..86c241cd0f56 100644
--- a/pkgs/os-specific/darwin/apple-sdk/cf-setup-hook.sh
+++ b/pkgs/os-specific/darwin/apple-sdk/cf-setup-hook.sh
@@ -1,5 +1,5 @@
 linkSystemCoreFoundationFramework() {
-  NIX_CFLAGS_COMPILE="-F@out@/Library/Frameworks $NIX_CFLAGS_COMPILE"
+  NIX_CFLAGS_COMPILE="-F@out@/Library/Frameworks${NIX_CFLAGS_COMPILE:+ }${NIX_CFLAGS_COMPILE-}"
   # gross! many symbols (such as _OBJC_CLASS_$_NSArray) are defined in system CF, but not
   # in the opensource release
   # if the package needs private headers, we assume they also want to link with system CF
diff --git a/pkgs/os-specific/darwin/apple-sdk/security-setup-hook.sh b/pkgs/os-specific/darwin/apple-sdk/security-setup-hook.sh
index ed9bdbd912db..35cea773f98b 100644
--- a/pkgs/os-specific/darwin/apple-sdk/security-setup-hook.sh
+++ b/pkgs/os-specific/darwin/apple-sdk/security-setup-hook.sh
@@ -2,7 +2,7 @@ noDeprecatedDeclarations() {
   # Security.framework has about 2000 deprecated constants, all of which the user will be
   # warned about at compilation time
   flag="-Wno-deprecated-declarations"
-  if [[ "$NIX_CFLAGS_COMPILE" != *$flag* ]]; then
+  if [[ "${NIX_CFLAGS_COMPILE-}" != *$flag* ]]; then
     NIX_CFLAGS_COMPILE+=" $flag"
   fi
 }

From ca782498a9532c48d8e12ce402813486ab90e7f0 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 18:24:49 -0500
Subject: [PATCH 16/17] emacs package setup hook: Fix

1. Make the test more robust

2. EMACSLOADPATH may be initially undefined.

3. did `targetOffset` twice when meant `hostOffset` too
---
 pkgs/build-support/emacs/setup-hook.sh | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/pkgs/build-support/emacs/setup-hook.sh b/pkgs/build-support/emacs/setup-hook.sh
index e1db3e828fd7..b55c18738023 100644
--- a/pkgs/build-support/emacs/setup-hook.sh
+++ b/pkgs/build-support/emacs/setup-hook.sh
@@ -1,11 +1,11 @@
 addEmacsVars () {
-  if test -d $1/share/emacs/site-lisp; then
-      export EMACSLOADPATH="$1/share/emacs/site-lisp:$EMACSLOADPATH"
+  if [[ -d "$1/share/emacs/site-lisp" ]]; then
+      export EMACSLOADPATH="$1/share/emacs/site-lisp${EMACSLOADPATH:+:}${EMACSLOADPATH-}"
   fi
 }
 
 # If this is for a wrapper derivation, emacs and the dependencies are all
 # run-time dependencies. If this is for precompiling packages into bytecode,
 # emacs is a compile-time dependency of the package.
-addEnvHooks "$targetOffset" addEmacsVars
+addEnvHooks "$hostOffset" addEmacsVars
 addEnvHooks "$targetOffset" addEmacsVars

From 784c3dc0f96ca85561e3a6805b0261d4bfb9f7e0 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 7 Nov 2019 19:39:03 -0500
Subject: [PATCH 17/17] qt5 qmake setup hook: `qmakeFlags` may be undefined

---
 pkgs/development/libraries/qt-5/hooks/qmake-hook.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh b/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
index b785a779c8bc..7f6ddb76ad57 100644
--- a/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
+++ b/pkgs/development/libraries/qt-5/hooks/qmake-hook.sh
@@ -1,6 +1,6 @@
 . @fix_qmake_libtool@
 
-qmakeFlags=( $qmakeFlags )
+qmakeFlags=( ${qmakeFlags-} )
 
 qmakePrePhase() {
     qmakeFlags=( \