Merge pull request #112928 from baloo/baloo/gcc/reproducible

stdenv: provide a deterministically built gcc

pkgs/development/compilers/gcc/8/default.nix

@@ -3,6 +3,7 @@
 , langObjC ? stdenv.targetPlatform.isDarwin
 , langObjCpp ? stdenv.targetPlatform.isDarwin
 , langGo ? false
+, reproducibleBuild ? true
 , profiledCompiler ? false
 , langJit ? false
 , staticCompiler ? false
@@ -45,6 +46,10 @@ assert langGo -> langCC;
 # threadsCross is just for MinGW
 assert threadsCross != null -> stdenv.targetPlatform.isWindows;
 
+# profiledCompiler builds inject non-determinism in one of the compilation stages.
+# If turned on, we can't provide reproducible builds anymore
+assert reproducibleBuild -> profiledCompiler == false;
+
 with lib;
 with builtins;