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prefix-never-matches.test
# RUN: cp -f %S/Inputs/prefix-never-matches.cpp %t.cpp
# RUN: %update_cc_test_checks %t.cpp 2>&1 | FileCheck %s
# RUN: FileCheck --input-file=%t.cpp %s --check-prefix=OUTPUT

# CHECK: WARNING: Prefix A had conflicting output
# OUTPUT-NOT: A: