haskell.compiler.ghc*: Add `variantSuffix`.

When debugging musl builds, I often have to sift through thousands of lines
of `nix-store -q --tree` or `nix-store -qR` output.
Until now, `pkgsMusl` and normal `pkgs` GHCs looked exactly the same in
there, making that task tough.

Same for `integer-simple`, which makes debugging `gmp` issues easier.

This commit introduces a suffix to tell them apart easily.

Note that this is different from `targetPrefix` which is for
cross-compilation, which `pkgsMusl` does not do.

For GHC HEAD, integer-simple no longer exists, instead we now have a
“bignum backend”, so we just call the integer-simple successor
native-bignum.

Co-Authored-By: sternenseemann <[e-mail]>

pkgs/development/compilers/ghc/8.10.2-binary.nix

···
     # nixpkgs uses for the respective system.
     defaultLibc = {
       i686-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-i386-deb9-linux.tar.xz";
           sha256 = "0bvwisl4w0z5z8z0da10m9sv0mhm9na2qm43qxr8zl23mn32mblx";
···
         ];
       };
       x86_64-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
           sha256 = "0chnzy9j23b2wa8clx5arwz8wnjfxyjmz9qkj548z14cqf13slcl";
···
         ];
       };
       armv7l-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-armv7-deb10-linux.tar.xz";
           sha256 = "1j41cq5d3rmlgz7hzw8f908fs79gc5mn3q5wz277lk8zdf19g75v";
···
         ];
       };
       aarch64-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-aarch64-deb10-linux.tar.xz";
           sha256 = "14smwl3741ixnbgi0l51a7kh7xjkiannfqx15b72svky0y4l3wjw";
···
         ];
       };
       x86_64-darwin = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-apple-darwin.tar.xz";
           sha256 = "1hngyq14l4f950hzhh2d204ca2gfc98pc9xdasxihzqd1jq75dzd";
···
     # Binary distributions for the musl libc for the respective system.
     musl = {
       x86_64-linux = {
+        variantSuffix = "-musl";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-alpine3.10-linux-integer-simple.tar.xz";
           sha256 = "0xpcbyaxqyhbl6f0i3s4rp2jm67nqpkfh2qlbj3i2fiaix89ml0l";
···
 
 stdenv.mkDerivation rec {
   inherit version;
-  pname = "ghc-binary";
+  pname = "ghc-binary${binDistUsed.variantSuffix}";
 
   src = fetchurl binDistUsed.src;
 

pkgs/development/compilers/ghc/8.10.7-binary.nix

···
     # nixpkgs uses for the respective system.
     defaultLibc = {
       i686-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-i386-deb9-linux.tar.xz";
           sha256 = "fbfc1ef194f4e7a4c0da8c11cc69b17458a4b928b609b3622c97acc4acd5c5ab";
···
         ];
       };
       x86_64-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
           sha256 = "a13719bca87a0d3ac0c7d4157a4e60887009a7f1a8dbe95c4759ec413e086d30";
···
         ];
       };
       armv7l-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-armv7-deb10-linux.tar.xz";
           sha256 = "3949c31bdf7d3b4afb765ea8246bca4ca9707c5d988d9961a244f0da100956a2";
···
         ];
       };
       aarch64-linux = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-aarch64-deb10-linux.tar.xz";
           sha256 = "fad2417f9b295233bf8ade79c0e6140896359e87be46cb61cd1d35863d9d0e55";
···
         ];
       };
       x86_64-darwin = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-apple-darwin.tar.xz";
           sha256 = "287db0f9c338c9f53123bfa8731b0996803ee50f6ee847fe388092e5e5132047";
···
         ];
       };
       aarch64-darwin = {
+        variantSuffix = "";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-aarch64-apple-darwin.tar.xz";
           sha256 = "dc469fc3c35fd2a33a5a575ffce87f13de7b98c2d349a41002e200a56d9bba1c";
···
     # Binary distributions for the musl libc for the respective system.
     musl = {
       x86_64-linux = {
+        variantSuffix = "-musl-integer-simple";
         src = {
           url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-alpine3.10-linux-integer-simple.tar.xz";
           sha256 = "16903df850ef73d5246f2ff169cbf57ecab76c2ac5acfa9928934282cfad575c";
···
 
 stdenv.mkDerivation rec {
   inherit version;
-  pname = "ghc-binary";
+  pname = "ghc-binary${binDistUsed.variantSuffix}";
 
   src = fetchurl binDistUsed.src;
 

pkgs/development/compilers/ghc/8.10.7.nix

···
     targetPackages.stdenv.cc.bintools.bintools
   ];
 
+  # Makes debugging easier to see which variant is at play in `nix-store -q --tree`.
+  variantSuffix = lib.concatStrings [
+    (lib.optionalString stdenv.hostPlatform.isMusl "-musl")
+    (lib.optionalString enableIntegerSimple "-integer-simple")
+  ];
+
 in
 stdenv.mkDerivation (rec {
   version = "8.10.7";
-  pname = "${targetPrefix}ghc";
+  pname = "${targetPrefix}ghc${variantSuffix}";
 
   src = fetchurl {
     url = "https://downloads.haskell.org/ghc/${version}/ghc-${version}-src.tar.xz";

pkgs/development/compilers/ghc/8.8.4.nix

···
     targetPackages.stdenv.cc.bintools.bintools
   ];
 
+  # Makes debugging easier to see which variant is at play in `nix-store -q --tree`.
+  variantSuffix = lib.concatStrings [
+    (lib.optionalString stdenv.hostPlatform.isMusl "-musl")
+    (lib.optionalString enableIntegerSimple "-integer-simple")
+  ];
+
 in
 stdenv.mkDerivation (rec {
   version = "8.8.4";
-  pname = "${targetPrefix}ghc";
+  pname = "${targetPrefix}ghc${variantSuffix}";
 
   src = fetchurl {
     url = "https://downloads.haskell.org/ghc/${version}/ghc-${version}-src.tar.xz";

pkgs/development/compilers/ghc/9.0.1.nix

···
     targetPackages.stdenv.cc.bintools.bintools
   ];
 
+  # Makes debugging easier to see which variant is at play in `nix-store -q --tree`.
+  variantSuffix = lib.concatStrings [
+    (lib.optionalString stdenv.hostPlatform.isMusl "-musl")
+    (lib.optionalString enableIntegerSimple "-integer-simple")
+  ];
+
 in
 stdenv.mkDerivation (rec {
   version = "9.0.1";
-  pname = "${targetPrefix}ghc";
+  pname = "${targetPrefix}ghc${variantSuffix}";
 
   src = fetchurl {
     url = "https://downloads.haskell.org/ghc/${version}/ghc-${version}-src.tar.xz";

pkgs/development/compilers/ghc/9.2.1.nix

···
     targetPackages.stdenv.cc.bintools.bintools
   ];
 
+  # Makes debugging easier to see which variant is at play in `nix-store -q --tree`.
+  variantSuffix = lib.concatStrings [
+    (lib.optionalString stdenv.hostPlatform.isMusl "-musl")
+    (lib.optionalString enableIntegerSimple "-integer-simple")
+  ];
+
 in
 stdenv.mkDerivation (rec {
   version = "9.2.0.20210821";
-  pname = "${targetPrefix}ghc";
+  pname = "${targetPrefix}ghc${variantSuffix}";
 
   src = fetchurl {
     url = "https://downloads.haskell.org/ghc/9.2.1-rc1/ghc-${version}-src.tar.xz";

pkgs/development/compilers/ghc/head.nix

···
     targetPackages.stdenv.cc.bintools.bintools
   ];
 
+  # Makes debugging easier to see which variant is at play in `nix-store -q --tree`.
+  variantSuffix = lib.concatStrings [
+    (lib.optionalString stdenv.hostPlatform.isMusl "-musl")
+    (lib.optionalString enableNativeBignum "-native-bignum")
+  ];
+
 in
 stdenv.mkDerivation (rec {
   inherit version;
   inherit (src) rev;
-  pname = "${targetPrefix}ghc";
+  pname = "${targetPrefix}ghc${variantSuffix}";
 
   src = fetchgit {
     url = "https://gitlab.haskell.org/ghc/ghc.git/";