[lld] [lld][ARM] Fix assertion when mixing ARM and Thumb objects (PR #101985)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,44 @@
+# REQUIRES: arm
+
+# RUN: rm -rf %t && split-file %s %t
+# RUN: llvm-mc -filetype=obj -arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %t/a.s -o %t1.o
+# RUN: llvm-mc -filetype=obj -arm-add-build-attributes -triple=armv7a-none-linux-gnueabi %t/b.s -o %t2.o
+# RUN: ld.lld -shared %t1.o %t2.o -o %t.so
+# RUN: llvm-objdump -d %t.so | FileCheck %s
+
+# Check that, when the input is a mixture of objects which can and cannot use
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MaskRay wrote:

In new tests, we use `## ` for non-CHECK-non-RUN comments.

https://github.com/llvm/llvm-project/pull/101985