llvmPackages_latest: move to aliases.nix

Because llvmPackages_latest is used in Nixpkgs, by quite a few
packages, it's difficult to keep it up to date, because updating it
requires some level of confidence that every package that uses it is
going to keep working after the update.  The result of this is that
llvmPackages_latest is not updated, and so we end up in the situation
that "latest" is two versions older than the latest version we
actually provide.  This is confusing and unexpected.

"But won't this end up fragmenting our LLVM versions, if every package
previously using _latest is separately pinned to LLVM 14?", I hear you
ask.  No.  That fragmentation is already happening, even with an
llvmPackages_latest, because packages that actually require the
_latest_ version of LLVM (15/16), have already been decoupled from
llvmPackages_latest since it hasn't been upgraded.  So like it or not,
we can't escape packages depending on specific recent LLVMs.  The only
real fix is to get better at keeping the default LLVM up to
date (which I'm reasonably confident we're getting into a better
position to be feasibly better able to do).

So, unless we want to double down on providing a confusingly named
"llvmPackages_latest" attribute that refers to some arbitrary LLVM
version that's probably not the latest one (or even the latest one
available in Nixpkgs), we only have two options here: either we don't
provide such an attribute at all, or we don't use it in Nixpkgs so we
don't become scared to bump it as soon as we have a new LLVM available.

6 files changed, 17 insertions, 25 deletions

diff --git a/nixos/modules/config/malloc.nix b/nixos/modules/config/malloc.nix
index b740ebfccb2..ae0661f472f 100644
--- a/nixos/modules/config/malloc.nix
+++ b/nixos/modules/config/malloc.nix
@@ -30,7 +30,7 @@ let
 
       systemPlatform = platformMap.${pkgs.stdenv.hostPlatform.system} or (throw "scudo not supported on ${pkgs.stdenv.hostPlatform.system}");
     in {
-      libPath = "${pkgs.llvmPackages_latest.compiler-rt}/lib/linux/libclang_rt.scudo-${systemPlatform}.so";
+      libPath = "${pkgs.llvmPackages_14.compiler-rt}/lib/linux/libclang_rt.scudo-${systemPlatform}.so";
       description = ''
         A user-mode allocator based on LLVM Sanitizer’s CombinedAllocator,
         which aims at providing additional mitigations against heap based
diff --git a/nixos/tests/darling.nix b/nixos/tests/darling.nix
index bc7b189372d..5665b4c2ffe 100644
--- a/nixos/tests/darling.nix
+++ b/nixos/tests/darling.nix
@@ -4,7 +4,7 @@ let
   # Well, we _can_ cross-compile from Linux :)
   hello = pkgs.runCommand "hello" {
     sdk = "${pkgs.darling.sdk}/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk";
-    nativeBuildInputs = with pkgs.llvmPackages_latest; [ clang-unwrapped lld ];
+    nativeBuildInputs = with pkgs.llvmPackages_14; [ clang-unwrapped lld ];
     src = pkgs.writeText "hello.c" ''
       #include <stdio.h>
       int main() {
diff --git a/pkgs/applications/terminal-emulators/foot/default.nix b/pkgs/applications/terminal-emulators/foot/default.nix
index 02de89a1b7a..b2b3526951a 100644
--- a/pkgs/applications/terminal-emulators/foot/default.nix
+++ b/pkgs/applications/terminal-emulators/foot/default.nix
@@ -23,7 +23,6 @@
 # for clang stdenv check
 , foot
 , llvmPackages
-, llvmPackages_latest
 }:
 
 let
@@ -187,10 +186,6 @@ stdenv.mkDerivation rec {
       inherit (llvmPackages) stdenv;
     };
 
-    clang-latest-compilation = foot.override {
-      inherit (llvmPackages_latest) stdenv;
-    };
-
     noPgo = foot.override {
       allowPgo = false;
     };
diff --git a/pkgs/os-specific/linux/keyutils/default.nix b/pkgs/os-specific/linux/keyutils/default.nix
index 54622253ed2..86b2535e1dd 100644
--- a/pkgs/os-specific/linux/keyutils/default.nix
+++ b/pkgs/os-specific/linux/keyutils/default.nix
@@ -18,7 +18,7 @@ stdenv.mkDerivation rec {
     ./conf-symlink.patch
     # This patch solves a duplicate symbol error when building with a clang stdenv
     # Before removing this patch, please ensure the package still builds by running eg.
-    # nix-build -E 'with import ./. {}; pkgs.keyutils.override { stdenv = pkgs.llvmPackages_latest.stdenv; }'
+    # nix-build -E 'with import ./. {}; pkgs.keyutils.override { stdenv = pkgs.clangStdenv; }'
     ./0001-Remove-unused-function-after_eq.patch
 
     # Fix build for s390-linux, where size_t is different from ptrdiff_t.
diff --git a/pkgs/top-level/aliases.nix b/pkgs/top-level/aliases.nix
index 12281c39e34..b7a1f91ebae 100644
--- a/pkgs/top-level/aliases.nix
+++ b/pkgs/top-level/aliases.nix
@@ -1886,6 +1886,7 @@ mapAliases ({
   inherit (stdenv) buildPlatform hostPlatform targetPlatform; # Added 2023-01-09
 
   # LLVM packages for (integration) testing that should not be used inside Nixpkgs:
+  llvmPackages_latest = llvmPackages_14;
   llvmPackages_git = recurseIntoAttrs (callPackage ../development/compilers/llvm/git {
     inherit (stdenvAdapters) overrideCC;
     buildLlvmTools = buildPackages.llvmPackages_git.tools;
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index be8e7b5ed27..9f1eab70884 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -14505,7 +14505,7 @@ with pkgs;
   ciao = callPackage ../development/compilers/ciao { };
 
   codon = callPackage ../development/compilers/codon {
-    inherit (llvmPackages_latest) lld stdenv;
+    inherit (llvmPackages_14) lld stdenv;
   };
 
   colm = callPackage ../development/compilers/colm { };
@@ -14568,7 +14568,7 @@ with pkgs;
   clang_16 = llvmPackages_16.clang;
 
   clang-tools = callPackage ../development/tools/clang-tools {
-    llvmPackages = llvmPackages_latest;
+    llvmPackages = llvmPackages_14;
   };
 
   clang-tools_5 = callPackage ../development/tools/clang-tools {
@@ -14620,13 +14620,13 @@ with pkgs;
   };
 
   clang-analyzer = callPackage ../development/tools/analysis/clang-analyzer {
-    llvmPackages = llvmPackages_latest;
-    inherit (llvmPackages_latest) clang;
+    llvmPackages = llvmPackages_14;
+    inherit (llvmPackages_14) clang;
   };
 
   clazy = callPackage ../development/tools/analysis/clazy {
-    llvmPackages = llvmPackages_latest;
-    stdenv = llvmPackages_latest.stdenv;
+    llvmPackages = llvmPackages_14;
+    stdenv = llvmPackages_14.stdenv;
   };
 
   #Use this instead of stdenv to build with clang
@@ -15580,7 +15580,7 @@ with pkgs;
   lld_15 = llvmPackages_15.lld;
   lld_16 = llvmPackages_16.lld;
 
-  lldb = llvmPackages_latest.lldb;
+  lldb = lldb_14;
   lldb_5 = llvmPackages_5.lldb;
   lldb_6 = llvmPackages_6.lldb;
   lldb_7 = llvmPackages_7.lldb;
@@ -15612,8 +15612,6 @@ with pkgs;
   llvm-manpages = llvmPackages.llvm-manpages;
 
   llvmPackages = let
-    latest_version = lib.toInt
-      (lib.versions.major llvmPackages_latest.llvm.version);
     # This returns the minimum supported version for the platform. The
     # assumption is that or any later version is good.
     choose = platform:
@@ -15622,7 +15620,7 @@ with pkgs;
       else if platform.isAndroid then 12
       else if platform.isLinux then 11
       else if platform.isWasm then 12
-      else latest_version;
+      else 14;
     # We take the "max of the mins". Why? Since those are lower bounds of the
     # supported version set, this is like intersecting those sets and then
     # taking the min bound of that.
@@ -15714,8 +15712,6 @@ with pkgs;
     targetLlvm = targetPackages.llvmPackages_16.llvm or llvmPackages_16.llvm;
   }));
 
-  llvmPackages_latest = llvmPackages_14;
-
   llvmPackages_rocm = recurseIntoAttrs (callPackage ../development/compilers/llvm/rocm { });
 
   lorri = callPackage ../tools/misc/lorri {
@@ -17354,7 +17350,7 @@ with pkgs;
   protege-distribution = callPackage ../development/web/protege-distribution { };
 
   umr = callPackage ../development/misc/umr {
-    llvmPackages = llvmPackages_latest;
+    llvmPackages = llvmPackages_14;
   };
 
   refurb = callPackage ../development/tools/refurb { };
@@ -17437,7 +17433,7 @@ with pkgs;
   buf-language-server = callPackage ../development/tools/language-servers/buf-language-server { };
 
   ccls = callPackage ../development/tools/language-servers/ccls {
-    llvmPackages = llvmPackages_latest;
+    llvmPackages = llvmPackages_14;
   };
 
   docker-compose-language-service = callPackage ../development/tools/language-servers/docker-compose-language-service { };
@@ -17998,7 +17994,7 @@ with pkgs;
 
   cvise = python3Packages.callPackage ../development/tools/misc/cvise {
     # cvise keeps up with fresh llvm releases and supports wide version range
-    inherit (llvmPackages_latest) llvm libclang;
+    inherit (llvmPackages_14) llvm libclang;
   };
 
   cwltool = callPackage ../applications/science/misc/cwltool { };
@@ -21384,7 +21380,7 @@ with pkgs;
   libcint = callPackage ../development/libraries/libcint { };
 
   libclc = callPackage ../development/libraries/libclc {
-    llvmPackages = llvmPackages_latest;
+    llvmPackages = llvmPackages_14;
   };
 
   libcli = callPackage ../development/libraries/libcli { };
@@ -22419,7 +22415,7 @@ with pkgs;
 
   libunwind =
     if stdenv.isDarwin then darwin.libunwind
-    else if stdenv.hostPlatform.system == "riscv32-linux" then llvmPackages_latest.libunwind
+    else if stdenv.hostPlatform.system == "riscv32-linux" then llvmPackages_14.libunwind
     else callPackage ../development/libraries/libunwind { };
 
   libuv = callPackage ../development/libraries/libuv {