diff --git a/pkgs/development/compilers/gcc/4.8/default.nix b/pkgs/development/compilers/gcc/4.8/default.nix
index 8eadfbf898c..cb0ae64f9d3 100644
--- a/pkgs/development/compilers/gcc/4.8/default.nix
+++ b/pkgs/development/compilers/gcc/4.8/default.nix
@@ -206,15 +206,22 @@ stdenv.mkDerivation ({
     ++ (optional (perl != null) perl)
     ++ (optional javaAwtGtk pkgconfig);
 
+  # For building runtime libs
+  depsBuildTarget =
+    if hostPlatform == buildPlatform then [
+      targetPackages.stdenv.cc.bintools # newly-built gcc will be used
+    ] else assert targetPlatform == hostPlatform; [ # build != host == target
+      stdenv.cc
+    ];
+
   buildInputs = [
     gmp mpfr libmpc libelf
+    targetPackages.stdenv.cc.bintools # For linking code at run-time
   ] ++ (optional (cloog != null) cloog)
     ++ (optional (isl != null) isl)
     ++ (optional (zlib != null) zlib)
     ++ (optionals langJava [ boehmgc zip unzip ])
     ++ (optionals javaAwtGtk ([ gtk2 libart_lgpl ] ++ xlibs))
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
diff --git a/pkgs/development/compilers/gcc/4.9/default.nix b/pkgs/development/compilers/gcc/4.9/default.nix
index 8a64cc79a9c..746beb01ecc 100644
--- a/pkgs/development/compilers/gcc/4.9/default.nix
+++ b/pkgs/development/compilers/gcc/4.9/default.nix
@@ -231,8 +231,6 @@ stdenv.mkDerivation ({
     ++ (optional (zlib != null) zlib)
     ++ (optionals langJava [ boehmgc zip unzip ])
     ++ (optionals javaAwtGtk ([ gtk2 libart_lgpl ] ++ xlibs))
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
@@ -259,7 +257,8 @@ stdenv.mkDerivation ({
     [
       "--with-gmp-include=${gmp.dev}/include"
       "--with-gmp-lib=${gmp.out}/lib"
-      "--with-mpfr=${mpfr.dev}"
+      "--with-mpfr-include=${mpfr.dev}/include"
+      "--with-mpfr-lib=${mpfr.out}/lib"
       "--with-mpc=${libmpc}"
     ] ++
     optional (libelf != null) "--with-libelf=${libelf}" ++
diff --git a/pkgs/development/compilers/gcc/5/default.nix b/pkgs/development/compilers/gcc/5/default.nix
index 5357f10ab5e..752e15c78cc 100644
--- a/pkgs/development/compilers/gcc/5/default.nix
+++ b/pkgs/development/compilers/gcc/5/default.nix
@@ -235,12 +235,10 @@ stdenv.mkDerivation ({
     ++ (optional (zlib != null) zlib)
     ++ (optionals langJava [ boehmgc zip unzip ])
     ++ (optionals javaAwtGtk ([ gtk2 libart_lgpl ] ++ xlibs))
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
 
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
-    ++ (optional hostPlatform.isDarwin targetPackages.stdenv.cc.bintools)
     ;
 
   NIX_LDFLAGS = stdenv.lib.optionalString  hostPlatform.isSunOS "-lm -ldl";
diff --git a/pkgs/development/compilers/gcc/6/default.nix b/pkgs/development/compilers/gcc/6/default.nix
index 557c8ceba8a..5900775b097 100644
--- a/pkgs/development/compilers/gcc/6/default.nix
+++ b/pkgs/development/compilers/gcc/6/default.nix
@@ -237,12 +237,9 @@ stdenv.mkDerivation ({
     ++ (optional (zlib != null) zlib)
     ++ (optionals langJava [ boehmgc zip unzip ])
     ++ (optionals javaAwtGtk ([ gtk2 libart_lgpl ] ++ xlibs))
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
-    ++ (optional hostPlatform.isDarwin targetPackages.stdenv.cc.bintools)
     ;
 
   NIX_LDFLAGS = stdenv.lib.optionalString  hostPlatform.isSunOS "-lm -ldl";
diff --git a/pkgs/development/compilers/gcc/7/default.nix b/pkgs/development/compilers/gcc/7/default.nix
index 85350f5a2b2..c409b145299 100644
--- a/pkgs/development/compilers/gcc/7/default.nix
+++ b/pkgs/development/compilers/gcc/7/default.nix
@@ -207,12 +207,9 @@ stdenv.mkDerivation ({
     targetPackages.stdenv.cc.bintools # For linking code at run-time
   ] ++ (optional (isl != null) isl)
     ++ (optional (zlib != null) zlib)
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
-    ++ (optional hostPlatform.isDarwin targetPackages.stdenv.cc.bintools)
     ;
 
   NIX_CFLAGS_COMPILE = stdenv.lib.optionalString (stdenv.cc.isClang && langFortran) "-Wno-unused-command-line-argument";
diff --git a/pkgs/development/compilers/gcc/8/default.nix b/pkgs/development/compilers/gcc/8/default.nix
index 9dac0235037..34d8c1eb1c2 100644
--- a/pkgs/development/compilers/gcc/8/default.nix
+++ b/pkgs/development/compilers/gcc/8/default.nix
@@ -202,12 +202,9 @@ stdenv.mkDerivation ({
     targetPackages.stdenv.cc.bintools # For linking code at run-time
   ] ++ (optional (isl != null) isl)
     ++ (optional (zlib != null) zlib)
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
-    ++ (optional hostPlatform.isDarwin targetPackages.stdenv.cc.bintools)
     ;
 
   NIX_LDFLAGS = stdenv.lib.optionalString  hostPlatform.isSunOS "-lm -ldl";
diff --git a/pkgs/development/compilers/gcc/snapshot/default.nix b/pkgs/development/compilers/gcc/snapshot/default.nix
index 96e05023743..d2f2c2ee558 100644
--- a/pkgs/development/compilers/gcc/snapshot/default.nix
+++ b/pkgs/development/compilers/gcc/snapshot/default.nix
@@ -172,12 +172,9 @@ stdenv.mkDerivation ({
     targetPackages.stdenv.cc.bintools # For linking code at run-time
   ] ++ (optional (isl != null) isl)
     ++ (optional (zlib != null) zlib)
-    ++ (optionals (targetPlatform != hostPlatform) [targetPackages.stdenv.cc.bintools])
-
     # The builder relies on GNU sed (for instance, Darwin's `sed' fails with
     # "-i may not be used with stdin"), and `stdenvNative' doesn't provide it.
     ++ (optional hostPlatform.isDarwin gnused)
-    ++ (optional hostPlatform.isDarwin targetPackages.stdenv.cc.bintools)
     ;
 
   NIX_LDFLAGS = stdenv.lib.optionalString  hostPlatform.isSunOS "-lm -ldl";