[llvm] [Release] Build default target during Phase 1 and 2 on AIX (PR #81009)

[Hubert Tong via llvm-commits]

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@@ -528,11 +528,11 @@ function build_llvmCore() {
     LitVerbose="-v"
 
     InstallTarget="install"
-    if [ "$Phase" -lt "3" ]; then
+    # compiler-rt builtins is needed on AIX to have a functional Phase 1 clang.
+    if [ "$Phase" -lt "3" ] && [ "$System" != "AIX" ]; then
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hubert-reinterpretcast wrote:

This is insulating AIX from the broader effects of the code here (to reduce the phase 1 and 2 builds) entirely. It should be possible to just add the necessary additional targets for AIX.

https://github.com/llvm/llvm-project/pull/81009