diff --git a/pkgs/development/compilers/gcc/4.8/default.nix b/pkgs/development/compilers/gcc/4.8/default.nix
index 2e46253c8ed..084ced822c7 100644
--- a/pkgs/development/compilers/gcc/4.8/default.nix
+++ b/pkgs/development/compilers/gcc/4.8/default.nix
@@ -210,7 +210,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/4.9/default.nix b/pkgs/development/compilers/gcc/4.9/default.nix
index a92b36c7236..a2a9f39a94e 100644
--- a/pkgs/development/compilers/gcc/4.9/default.nix
+++ b/pkgs/development/compilers/gcc/4.9/default.nix
@@ -216,7 +216,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/5/default.nix b/pkgs/development/compilers/gcc/5/default.nix
index 8f318e60e95..775245aae42 100644
--- a/pkgs/development/compilers/gcc/5/default.nix
+++ b/pkgs/development/compilers/gcc/5/default.nix
@@ -223,7 +223,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/6/default.nix b/pkgs/development/compilers/gcc/6/default.nix
index 3126747eb00..3f5644e9450 100644
--- a/pkgs/development/compilers/gcc/6/default.nix
+++ b/pkgs/development/compilers/gcc/6/default.nix
@@ -225,7 +225,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/7/default.nix b/pkgs/development/compilers/gcc/7/default.nix
index b57215c9d6c..f780bfdfc76 100644
--- a/pkgs/development/compilers/gcc/7/default.nix
+++ b/pkgs/development/compilers/gcc/7/default.nix
@@ -202,7 +202,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/8/default.nix b/pkgs/development/compilers/gcc/8/default.nix
index 0859730534e..dc051d9c4b6 100644
--- a/pkgs/development/compilers/gcc/8/default.nix
+++ b/pkgs/development/compilers/gcc/8/default.nix
@@ -191,7 +191,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/9/default.nix b/pkgs/development/compilers/gcc/9/default.nix
index 5abe01e36bb..57f4a72c135 100644
--- a/pkgs/development/compilers/gcc/9/default.nix
+++ b/pkgs/development/compilers/gcc/9/default.nix
@@ -190,7 +190,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;
diff --git a/pkgs/development/compilers/gcc/snapshot/default.nix b/pkgs/development/compilers/gcc/snapshot/default.nix
index 3c74a6d14e2..ef55806ce08 100644
--- a/pkgs/development/compilers/gcc/snapshot/default.nix
+++ b/pkgs/development/compilers/gcc/snapshot/default.nix
@@ -157,7 +157,7 @@ stdenv.mkDerivation ({
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;
 
   buildFlags = optional
-    (hostPlatform == buildPlatform)
+    (targetPlatform == hostPlatform && hostPlatform == buildPlatform)
     (if profiledCompiler then "profiledbootstrap" else "bootstrap");
 
   dontStrip = !stripped;