diff --git a/pkgs/development/compilers/gcc/4.5/default.nix b/pkgs/development/compilers/gcc/4.5/default.nix
index 0482ff772d6..3e20cade8ae 100644
--- a/pkgs/development/compilers/gcc/4.5/default.nix
+++ b/pkgs/development/compilers/gcc/4.5/default.nix
@@ -151,12 +151,7 @@ stdenv.mkDerivation ({
     ;
 
   postPatch =
-    if (stdenv.system == "i586-pc-gnu"
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (targetPlatform != hostPlatform && targetPlatform.config == "i586-pc-gnu"
-            && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/4.8/default.nix b/pkgs/development/compilers/gcc/4.8/default.nix
index 06068386070..79e4c82852b 100644
--- a/pkgs/development/compilers/gcc/4.8/default.nix
+++ b/pkgs/development/compilers/gcc/4.8/default.nix
@@ -193,11 +193,7 @@ stdenv.mkDerivation ({
   libc_dev = stdenv.cc.libc_dev;
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/4.9/default.nix b/pkgs/development/compilers/gcc/4.9/default.nix
index 1fab985473e..4936a6a3a9a 100644
--- a/pkgs/development/compilers/gcc/4.9/default.nix
+++ b/pkgs/development/compilers/gcc/4.9/default.nix
@@ -188,11 +188,7 @@ stdenv.mkDerivation ({
   libc_dev = stdenv.cc.libc_dev;
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/5/default.nix b/pkgs/development/compilers/gcc/5/default.nix
index 6e3e7d0b099..79dcb67ff72 100644
--- a/pkgs/development/compilers/gcc/5/default.nix
+++ b/pkgs/development/compilers/gcc/5/default.nix
@@ -204,11 +204,7 @@ stdenv.mkDerivation ({
   '';
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/6/default.nix b/pkgs/development/compilers/gcc/6/default.nix
index 67b7cf61c5a..857f9e1a2b6 100644
--- a/pkgs/development/compilers/gcc/6/default.nix
+++ b/pkgs/development/compilers/gcc/6/default.nix
@@ -204,11 +204,7 @@ stdenv.mkDerivation ({
   '';
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/7/default.nix b/pkgs/development/compilers/gcc/7/default.nix
index 2a034954f73..a3435cc4f16 100644
--- a/pkgs/development/compilers/gcc/7/default.nix
+++ b/pkgs/development/compilers/gcc/7/default.nix
@@ -204,11 +204,7 @@ stdenv.mkDerivation ({
   '';
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.
diff --git a/pkgs/development/compilers/gcc/snapshot/default.nix b/pkgs/development/compilers/gcc/snapshot/default.nix
index 693474bfb5e..884bccd37f0 100644
--- a/pkgs/development/compilers/gcc/snapshot/default.nix
+++ b/pkgs/development/compilers/gcc/snapshot/default.nix
@@ -183,11 +183,7 @@ stdenv.mkDerivation ({
   hardeningDisable = [ "format" ];
 
   postPatch =
-    if (hostPlatform.isHurd
-        || (libcCross != null                  # e.g., building `gcc.crossDrv'
-            && libcCross ? crossConfig
-            && libcCross.crossConfig == "i586-pc-gnu")
-        || (crossGNU && libcCross != null))
+    if targetPlatform.isHurd
     then
       # On GNU/Hurd glibc refers to Hurd & Mach headers and libpthread is not
       # in glibc, so add the right `-I' flags to the default spec string.