From d3114e05d777039ae04a9c39ce798140ccb81ed9 Mon Sep 17 00:00:00 2001
From: Randy Eckenrode <randy@largeandhighquality.com>
Date: Mon, 23 Sep 2024 22:06:54 -0400
Subject: [PATCH] llvmPackages.compiler-rt: align Darwin bootstrap with other
 platforms

Instead of using overrides in the stdenv bootstrap, Darwin will be
relying on the LLVM bootstrap to build compiler-rt. The only special
handling it needs is to use a stdenv with a bootstrap SDK instead of the
default one (to avoid infinite recursions).
---
 .../compilers/llvm/common/default.nix           | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/pkgs/development/compilers/llvm/common/default.nix b/pkgs/development/compilers/llvm/common/default.nix
index c863d0d8a82a..35525e379f2b 100644
--- a/pkgs/development/compilers/llvm/common/default.nix
+++ b/pkgs/development/compilers/llvm/common/default.nix
@@ -1012,14 +1012,11 @@ let
         let
           # temp rename to avoid infinite recursion
           stdenv =
-            if args.stdenv.hostPlatform.useLLVM or false then
+            # Darwin needs to use a bootstrap stdenv to avoid an infinite recursion when cross-compiling.
+            if args.stdenv.hostPlatform.isDarwin then
+              overrideCC darwin.bootstrapStdenv buildLlvmTools.clangWithLibcAndBasicRtAndLibcxx
+            else if args.stdenv.hostPlatform.useLLVM or false then
               overrideCC args.stdenv buildLlvmTools.clangWithLibcAndBasicRtAndLibcxx
-            else if
-              lib.versionAtLeast metadata.release_version "16"
-              && args.stdenv.hostPlatform.isDarwin
-              && args.stdenv.hostPlatform.isStatic
-            then
-              overrideCC args.stdenv buildLlvmTools.clangNoCompilerRtWithLibc
             else
               args.stdenv;
         in
@@ -1038,10 +1035,10 @@ let
         patches = compiler-rtPatches;
         doFakeLibgcc = stdenv.hostPlatform.useLLVM or false;
         stdenv =
-          if stdenv.hostPlatform.isDarwin && stdenv.hostPlatform == stdenv.buildPlatform then
-            stdenv
+          # Darwin needs to use a bootstrap stdenv to avoid an infinite recursion when cross-compiling.
+          if stdenv.hostPlatform.isDarwin then
+            overrideCC darwin.bootstrapStdenv buildLlvmTools.clangNoLibcNoRt
           else
-            # TODO: make this branch unconditional next rebuild
             overrideCC stdenv buildLlvmTools.clangNoLibcNoRt;
       };