`%t/basics` already exists - it would be nice to be able to examine it afterward
Differential Revision: https://reviews.llvm.org/D112392
## Extern symbols aren't stripped from executables with -export_dynamic
# RUN: %lld -lSystem -dead_strip -export_dynamic -u _ref_private_extern_u \
-# RUN: %t/basics.o -o %t/basics
-# RUN: llvm-objdump --syms --section-headers %t/basics | \
+# RUN: %t/basics.o -o %t/basics-export-dyn
+# RUN: llvm-objdump --syms --section-headers %t/basics-export-dyn | \
# RUN: FileCheck --check-prefix=EXECDYN %s
# EXECDYN-LABEL: Sections:
# EXECDYN-LABEL: Name