diff --git a/pkgs/applications/graphics/leocad/default.nix b/pkgs/applications/graphics/leocad/default.nix
index 884dc1158534..96384765bd03 100644
--- a/pkgs/applications/graphics/leocad/default.nix
+++ b/pkgs/applications/graphics/leocad/default.nix
@@ -17,6 +17,7 @@ stdenv.mkDerivation rec {
   buildInputs = [ qt4 qmake4Hook zlib ];
 
   postPatch = ''
+    sed '1i#include <cmath>' -i common/camera.cpp
     substituteInPlace common/camera.cpp --replace "isnan(" "std::isnan("
     export qmakeFlags="$qmakeFlags INSTALL_PREFIX=$out"
   '';
diff --git a/pkgs/applications/graphics/photivo/default.nix b/pkgs/applications/graphics/photivo/default.nix
index 12816ba96af4..d84363df899e 100644
--- a/pkgs/applications/graphics/photivo/default.nix
+++ b/pkgs/applications/graphics/photivo/default.nix
@@ -10,15 +10,19 @@ stdenv.mkDerivation rec {
     sha256 = "0f6y18k7db2ci6xn664zcwm1g1k04sdv7gg1yd5jk41bndjb7z8h";
   };
 
-  nativeBuildInputs = [ cmake pkgconfig ];
-
-  buildInputs = [ qt4 fftw graphicsmagick_q16 lcms2 lensfun libjpeg exiv2 liblqr1 ];
-  patchPhase = '' # kinda icky
+  postPatch = '' # kinda icky
     sed -e '/("@INSTALL@")/d' \
         -e s,@INSTALL@,$out/share/photivo, \
         -i Sources/ptSettings.cpp
+    sed '1i#include <math.h>' -i Sources/filters/ptFilter_StdCurve.cpp
   '';
 
+  nativeBuildInputs = [ cmake pkgconfig ];
+
+  buildInputs = [ qt4 fftw graphicsmagick_q16 lcms2 lensfun libjpeg exiv2 liblqr1 ];
+
+  enableParallelBuilding = true;
+
   meta = with stdenv.lib; {
       platforms = platforms.linux;
       maintainers = [ maintainers.mornfall ];
diff --git a/pkgs/applications/misc/cli-visualizer/default.nix b/pkgs/applications/misc/cli-visualizer/default.nix
index 6b9856a996ac..1c7fd62f8ecc 100644
--- a/pkgs/applications/misc/cli-visualizer/default.nix
+++ b/pkgs/applications/misc/cli-visualizer/default.nix
@@ -10,6 +10,10 @@ stdenv.mkDerivation rec {
     sha256 = "16768gyi85mkizfn874q2q9xf32knw08z27si3k5bk99492dxwzw";
   };
 
+  postPatch = ''
+    sed '1i#include <cmath>' -i src/Transformer/SpectrumCircleTransformer.cpp
+  '';
+
   buildInputs = [ fftw ncurses libpulseaudio ];
 
   buildFlags = [ "ENABLE_PULSE=1" ];
diff --git a/pkgs/applications/misc/termite/default.nix b/pkgs/applications/misc/termite/default.nix
index 33bc29f871c7..33c42e3dc1dd 100644
--- a/pkgs/applications/misc/termite/default.nix
+++ b/pkgs/applications/misc/termite/default.nix
@@ -13,6 +13,8 @@ let
       sha256 = "1cw4yw7n9m2si8b7zcfyz9pyihncabxm5g39v1mxslfajxgwzmd8";
     };
 
+    postPatch = "sed '1i#include <math.h>' -i termite.cc";
+
     makeFlags = [ "VERSION=v${version}" "PREFIX=" "DESTDIR=$(out)" ];
 
     buildInputs = [ pkgconfig vte gtk3 ncurses ];
diff --git a/pkgs/applications/science/robotics/qgroundcontrol/default.nix b/pkgs/applications/science/robotics/qgroundcontrol/default.nix
index b67da5b55162..37e9c9c858f1 100644
--- a/pkgs/applications/science/robotics/qgroundcontrol/default.nix
+++ b/pkgs/applications/science/robotics/qgroundcontrol/default.nix
@@ -27,6 +27,11 @@ stdenv.mkDerivation rec {
  ] ++ qtInputs;
 
   patches = [ ./0001-fix-gcc-cmath-namespace-issues.patch ];
+  postPatch = ''
+    sed '1i#include <cmath>' -i src/Vehicle/Vehicle.cc \
+      -i src/comm/{QGCFlightGearLink,QGCJSBSimLink}.cc \
+      -i src/{uas/UAS,ui/QGCDataPlot2D}.cc
+  '';
 
   preConfigure = ''
     mkdir build
diff --git a/pkgs/applications/video/simplescreenrecorder/default.nix b/pkgs/applications/video/simplescreenrecorder/default.nix
index a5fb122cf897..3ea04a39393b 100644
--- a/pkgs/applications/video/simplescreenrecorder/default.nix
+++ b/pkgs/applications/video/simplescreenrecorder/default.nix
@@ -11,11 +11,15 @@ stdenv.mkDerivation rec {
     sha256 = "1d89ncspjd8c4mckf0nb6y3hrxpv4rjpbj868pznhvfmdgr5nvql";
   };
 
+  postPatch = "sed '1i#include <random>' -i src/Benchmark.cpp";
+
   buildInputs = [
     alsaLib ffmpeg libjack2 libX11 libXext libXfixes mesa pkgconfig
     libpulseaudio qt4
   ];
 
+  enableParallelBuilding = true;
+
   meta = with stdenv.lib; {
     description = "A screen recorder for Linux";
     homepage = http://www.maartenbaert.be/simplescreenrecorder;
diff --git a/pkgs/desktops/kde-5/plasma-5.6/plasma-desktop/default.nix b/pkgs/desktops/kde-5/plasma-5.6/plasma-desktop/default.nix
index 618e7387e62c..2a1d95806c10 100644
--- a/pkgs/desktops/kde-5/plasma-5.6/plasma-desktop/default.nix
+++ b/pkgs/desktops/kde-5/plasma-5.6/plasma-desktop/default.nix
@@ -34,6 +34,9 @@ plasmaPackage rec {
     })
     ./0003-tzdir.patch
   ];
+  postPatch = ''
+    sed '1i#include <cmath>' -i kcms/touchpad/src/backends/x11/synapticstouchpad.cpp
+  '';
   NIX_CFLAGS_COMPILE = [ "-I${xorgserver.dev}/include/xorg" ];
   cmakeFlags = [
     "-DEvdev_INCLUDE_DIRS=${xf86inputevdev.dev}/include/xorg"
diff --git a/pkgs/development/libraries/botan/generic.nix b/pkgs/development/libraries/botan/generic.nix
index 823e50e32272..4a4ec5d9fe9c 100644
--- a/pkgs/development/libraries/botan/generic.nix
+++ b/pkgs/development/libraries/botan/generic.nix
@@ -2,6 +2,7 @@
 # Passed by version specific builders
 , baseVersion, revision, sha256
 , extraConfigureFlags ? ""
+, postPatch ? null
 , ...
 }:
 
@@ -17,6 +18,7 @@ stdenv.mkDerivation rec {
     ];
     inherit sha256;
   };
+  inherit postPatch;
 
   buildInputs = [ python bzip2 zlib gmp openssl boost ];
 
diff --git a/pkgs/development/libraries/botan/unstable.nix b/pkgs/development/libraries/botan/unstable.nix
index dd185f21035d..d952b50aeb8e 100644
--- a/pkgs/development/libraries/botan/unstable.nix
+++ b/pkgs/development/libraries/botan/unstable.nix
@@ -5,4 +5,5 @@ callPackage ./generic.nix (args // {
   revision = "29";
   sha256 = "157bp8716h17agrxyj7xpsj2i5sqhafj1nfx4gpzccx7y2kyq176";
   openssl = null;
+  postPatch = "sed '1i#include <cmath>' -i src/tests/test_bigint.cpp";
 })
diff --git a/pkgs/development/libraries/xgboost/default.nix b/pkgs/development/libraries/xgboost/default.nix
index e3c5d7573107..4ba366be56f0 100644
--- a/pkgs/development/libraries/xgboost/default.nix
+++ b/pkgs/development/libraries/xgboost/default.nix
@@ -11,6 +11,8 @@ stdenv.mkDerivation rec {
     sha256 = "1d7lnbwxwakclqqfjwyk9w3wd2clkihdr6ljs5z08ydiaspri093";
   };
 
+  postPatch = "sed '1i#include <cmath>' -i src/tree/param.h";
+
   enableParallelBuilding = true;
 
   installPhase = ''
diff --git a/pkgs/development/tools/misc/hydra/default.nix b/pkgs/development/tools/misc/hydra/default.nix
index 510a0679527e..a4f1a96c6a4c 100644
--- a/pkgs/development/tools/misc/hydra/default.nix
+++ b/pkgs/development/tools/misc/hydra/default.nix
@@ -3,7 +3,7 @@
 , gitAndTools, mercurial, darcs, subversion, bazaar, openssl, bzip2, libxslt
 , guile, perl, postgresql92, aws-sdk-cpp, nukeReferences, git, boehmgc
 , docbook_xsl, openssh, gnused, coreutils, findutils, gzip, lzma, gnutar
-, rpm, dpkg, cdrkit }:
+, rpm, dpkg, cdrkit, fetchpatch }:
 
 with stdenv;
 
@@ -70,6 +70,12 @@ in releaseTools.nixBuild rec {
     sha256 = "0ngipzm2i2vz5ygfd70hh82d027snpl85r8ncn1rxlkak0g8fxsl";
   };
 
+  patches = [(fetchpatch {
+    name = "cmath.diff";
+    url = https://github.com/vcunat/hydra/commit/3c6fca1ba299.diff; # https://github.com/NixOS/hydra/pull/337
+    sha256 = "02m9q304ay45s7xfkm2y7lppakrkx3hrq39mm6348isnbqmbarc0";
+  })];
+
   buildInputs =
     [ makeWrapper autoconf automake libtool unzip nukeReferences pkgconfig sqlite libpqxx
       gitAndTools.topGit mercurial darcs subversion bazaar openssl bzip2 libxslt
diff --git a/pkgs/games/cataclysm-dda/default.nix b/pkgs/games/cataclysm-dda/default.nix
index 3956c994531e..b46114ec62be 100644
--- a/pkgs/games/cataclysm-dda/default.nix
+++ b/pkgs/games/cataclysm-dda/default.nix
@@ -21,6 +21,9 @@ stdenv.mkDerivation rec {
     sed -i Makefile \
       -e 's,-Werror,,g' \
       -e 's,\(DATA_PREFIX=$(PREFIX)/share/\)cataclysm-dda/,\1,g'
+
+    sed '1i#include <cmath>' \
+      -i src/{crafting,skill,weather_data,melee,vehicle,overmap,iuse_actor}.cpp
   '';
 
   makeFlags = "PREFIX=$(out) LUA=1 TILES=1 SOUND=1 RELEASE=1 USE_HOME_DIR=1";
diff --git a/pkgs/games/dwarf-fortress/dfhack/default.nix b/pkgs/games/dwarf-fortress/dfhack/default.nix
index 3d3b1c4d9aa8..1ee0f829571d 100644
--- a/pkgs/games/dwarf-fortress/dfhack/default.nix
+++ b/pkgs/games/dwarf-fortress/dfhack/default.nix
@@ -39,6 +39,7 @@ in stdenv.mkDerivation rec {
   };
 
   patches = [ ./use-system-libraries.patch ];
+  postPatch = "sed '1i#include <math.h>' -i plugins/3dveins.cpp";
 
   nativeBuildInputs = [ cmake perl XMLLibXML XMLLibXSLT fakegit ];
   # we can't use native Lua; upstream uses private headers
diff --git a/pkgs/games/dwarf-fortress/unfuck.nix b/pkgs/games/dwarf-fortress/unfuck.nix
index 1d6ea1196dab..5b2327c2ff54 100644
--- a/pkgs/games/dwarf-fortress/unfuck.nix
+++ b/pkgs/games/dwarf-fortress/unfuck.nix
@@ -13,6 +13,8 @@ stdenv.mkDerivation {
     sha256 = "12bqh3k4wsk1c0bz2zly8h0ilbsdmsbwr9cdjc6i7liwg9906g7i";
   };
 
+  postPatch = "sed '1i#include <math.h>' -i g_src/ttf_manager.cpp";
+
   cmakeFlags = [
     "-DGTK2_GLIBCONFIG_INCLUDE_DIR=${glib.out}/lib/glib-2.0/include"
     "-DGTK2_GDKCONFIG_INCLUDE_DIR=${gtk2.out}/lib/gtk-2.0/include"
diff --git a/pkgs/games/openspades/default.nix b/pkgs/games/openspades/default.nix
index 2203bb6337eb..d263be3ec115 100644
--- a/pkgs/games/openspades/default.nix
+++ b/pkgs/games/openspades/default.nix
@@ -16,7 +16,10 @@ stdenv.mkDerivation rec {
   postPatch = ''
     substituteInPlace Sources/Client/Client_Input.cpp --replace "isnan(" "std::isnan("
     substituteInPlace Sources/Client/Corpse.cpp --replace "isnan(" "std::isnan("
-    substituteInPlace Sources/Draw/SWMapRenderer.cpp --replace "isnan(" "std::isnan(" --replace "isinf(" "std::isinf("
+    substituteInPlace Sources/Draw/SWMapRenderer.cpp \
+      --replace "isnan(" "std::isnan(" --replace "isinf(" "std::isinf("
+    sed '1i#include <cmath>' -i Sources/Client/{Player,Client_Input,Corpse}.cpp \
+      -i Sources/Draw/SWMapRenderer.cpp
   '';
 
   nativeBuildInputs = 
diff --git a/pkgs/games/openspades/git.nix b/pkgs/games/openspades/git.nix
index 8212f160cda8..7d76573f7345 100644
--- a/pkgs/games/openspades/git.nix
+++ b/pkgs/games/openspades/git.nix
@@ -14,6 +14,8 @@ stdenv.mkDerivation rec {
     sha256 = "0vyvmgim03q8pcmfa1i0njr4w1lpjq5g3b47f67v9b5c5jcjycwn";
   };
 
+  postPatch = "sed '1i#include <cmath>' -i Sources/Client/{,Client}Player.cpp";
+
   nativeBuildInputs = 
     with stdenv.lib;
     [ cmake curl glew makeWrapper mesa SDL2 SDL2_image unzip wget zlib ]
diff --git a/pkgs/games/the-butterfly-effect/default.nix b/pkgs/games/the-butterfly-effect/default.nix
index 8775fb103d8d..cf587ce89dd6 100644
--- a/pkgs/games/the-butterfly-effect/default.nix
+++ b/pkgs/games/the-butterfly-effect/default.nix
@@ -9,8 +9,12 @@ stdenv.mkDerivation rec {
     sha256 = "1cs4q9qiakfd2m1lvfsvfgf8yvhxzmc06glng5d80piwyn6ymzxg";
   };
 
+  postPatch = "sed '1i#include <vector>' -i src/model/World.h";
+
   buildInputs = [ qt4 box2d which cmake ];
 
+  enableParallelBuilding = true;
+
   installPhase = ''
     make DESTDIR=.. install
     mkdir -p $out/bin
diff --git a/pkgs/misc/emulators/higan/default.nix b/pkgs/misc/emulators/higan/default.nix
index 1395e3ac3efe..77392913cb1a 100644
--- a/pkgs/misc/emulators/higan/default.nix
+++ b/pkgs/misc/emulators/higan/default.nix
@@ -21,6 +21,7 @@ stdenv.mkDerivation rec {
   };
 
   patches = [ ./0001-change-flags.diff ];
+  postPatch = "sed '1i#include <cmath>' -i higan/fc/ppu/ppu.cpp";
 
   buildInputs =
   [ p7zip pkgconfig libX11 libXv udev mesa SDL libao openal libpulseaudio gtk gtksourceview ];
diff --git a/pkgs/misc/emulators/pcsx2/default.nix b/pkgs/misc/emulators/pcsx2/default.nix
index 1b95bca643c7..673e4c3ed087 100644
--- a/pkgs/misc/emulators/pcsx2/default.nix
+++ b/pkgs/misc/emulators/pcsx2/default.nix
@@ -15,6 +15,8 @@ stdenv.mkDerivation rec {
     sha256 = "0s7mxq2cgzwjfsq0vhpz6ljk7wr725nxg48128iyirf85585l691";
   };
 
+  postPatch = "sed '1i#include \"x86intrin.h\"' -i common/src/x86emitter/cpudetect.cpp";
+
   configurePhase = ''
     mkdir -p build
     cd build
@@ -50,6 +52,8 @@ stdenv.mkDerivation rec {
     soundtouch wxGTK30 zlib
   ];
 
+  enableParallelBuilding = true;
+
   meta = with stdenv.lib; {
     description = "Playstation 2 emulator";
     longDescription= ''
diff --git a/pkgs/os-specific/linux/sysdig/default.nix b/pkgs/os-specific/linux/sysdig/default.nix
index 8296ec62c5b2..82e088b76c20 100644
--- a/pkgs/os-specific/linux/sysdig/default.nix
+++ b/pkgs/os-specific/linux/sysdig/default.nix
@@ -18,6 +18,9 @@ stdenv.mkDerivation {
   src = fetchurl {
     inherit (s) url sha256;
   };
+  postPatch = ''
+    sed '1i#include <cmath>' -i userspace/libsinsp/{cursesspectro,filterchecks}.cpp
+  '';
 
   cmakeFlags = [
     "-DUSE_BUNDLED_DEPS=OFF"