[lld] 7ffeab3 - [LLD][ELF] Generically report "address assignment did not converge" (#128774)

[via llvm-commits]

Author: Daniel Thornburgh
Date: 2025-02-26T09:10:53-08:00
New Revision: 7ffeab3121c984cc00f79b0a78f372a4f7526e3b

URL: https://github.com/llvm/llvm-project/commit/7ffeab3121c984cc00f79b0a78f372a4f7526e3b
DIFF: https://github.com/llvm/llvm-project/commit/7ffeab3121c984cc00f79b0a78f372a4f7526e3b.diff

LOG: [LLD][ELF] Generically report "address assignment did not converge" (#128774)

There are considerable number of changes done in the address assignment
fixed point loop, and errors in any of them could cause address
assignment not to converge. However, this is reported to the user as
either "thunk creation not converged" or "relaxation not converged".

We saw a confused bug about this in the wild when spilling failed to
converge. (I'm working on a fix for that.)

We may eventually want a complete reason system when reporting address
assignment taking too many passes, but in the interim it seems prudent
to generalize the error message to "address assignment did not
converge".

Added: 
    

Modified: 
    lld/ELF/Writer.cpp
    lld/test/ELF/linkerscript/symbol-assign-many-passes2.test

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index a2c49343e5c8d..0d61e8d8d91a4 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -1531,8 +1531,7 @@ template <class ELFT> void Writer<ELFT>::finalizeAddressDependentContent() {
     // With Thunk Size much smaller than branch range we expect to
     // converge quickly; if we get to 30 something has gone wrong.
     if (changed && pass >= 30) {
-      Err(ctx) << (ctx.target->needsThunks ? "thunk creation not converged"
-                                           : "relaxation not converged");
+      Err(ctx) << "address assignment did not converge";
       break;
     }
 

diff  --git a/lld/test/ELF/linkerscript/symbol-assign-many-passes2.test b/lld/test/ELF/linkerscript/symbol-assign-many-passes2.test
index 18dc5019ee1eb..b5ca48b7cd295 100644
--- a/lld/test/ELF/linkerscript/symbol-assign-many-passes2.test
+++ b/lld/test/ELF/linkerscript/symbol-assign-many-passes2.test
@@ -6,7 +6,7 @@
 ## arm-thunk-many-passes.s is worst case case of thunk generation that takes 9
 ## passes to converge. It takes a few more passes to make symbol assignment
 ## converge. Test that
-## 1. we don't error that "thunk creation not converged".
+## 1. we don't error that "address assignment did not converge".
 ## 2. we check convergence of symbols defined in an output section descriptor.
 
 # CHECK: 01011050 T a