diff --git a/pkgs/development/compilers/gcc/4.8/default.nix b/pkgs/development/compilers/gcc/4.8/default.nix
index 1ee052952010..324599e49821 100644
--- a/pkgs/development/compilers/gcc/4.8/default.nix
+++ b/pkgs/development/compilers/gcc/4.8/default.nix
@@ -208,7 +208,7 @@ 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 56860ca5cc66..9d4d8a9b6ac2 100644
--- a/pkgs/development/compilers/gcc/4.9/default.nix
+++ b/pkgs/development/compilers/gcc/4.9/default.nix
@@ -214,7 +214,7 @@ 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 5dc574d37023..d809c6c4e364 100644
--- a/pkgs/development/compilers/gcc/5/default.nix
+++ b/pkgs/development/compilers/gcc/5/default.nix
@@ -221,7 +221,7 @@ 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 a3030366be65..1eec43cb320a 100644
--- a/pkgs/development/compilers/gcc/6/default.nix
+++ b/pkgs/development/compilers/gcc/6/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/7/default.nix b/pkgs/development/compilers/gcc/7/default.nix
index 49a43b337739..7a4b0ed32228 100644
--- a/pkgs/development/compilers/gcc/7/default.nix
+++ b/pkgs/development/compilers/gcc/7/default.nix
@@ -200,7 +200,7 @@ 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 9b36412efd4d..c0df37bd5f8f 100644
--- a/pkgs/development/compilers/gcc/8/default.nix
+++ b/pkgs/development/compilers/gcc/8/default.nix
@@ -184,7 +184,7 @@ 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 a5279504811d..23a5eeafb8b8 100644
--- a/pkgs/development/compilers/gcc/9/default.nix
+++ b/pkgs/development/compilers/gcc/9/default.nix
@@ -183,7 +183,7 @@ 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 286047a9f4aa..d073edfb09c8 100644
--- a/pkgs/development/compilers/gcc/snapshot/default.nix
+++ b/pkgs/development/compilers/gcc/snapshot/default.nix
@@ -155,7 +155,7 @@ 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;