Don't fail the shared_ptr test if libc++ has insufficient debug info.

Don't fail the shared_ptr test if libc++ has insufficient debug info. This addresses https://bugs.llvm.org/show_bug.cgi?id=48937 Differential Revision: https://reviews.llvm.org/D100610 (cherry picked from commit 0e83780)

Author: Sterling-Augustine

libcxx/test/libcxx/gdb/gdb_pretty_printer_test.py

@@ -37,6 +37,23 @@ def invoke(self, arg, from_tty):
  compare_frame = gdb.newest_frame().older()
  testcase_frame = compare_frame.older()
  test_loc = testcase_frame.find_sal()
+
+ expectation_val = compare_frame.read_var("expectation")
+ check_literal = expectation_val.string(encoding="utf-8")
+
+ # Heuristic to determine if libc++ itself has debug
+ # info. If it doesn't, then anything normally homed there
+ # won't be found, and the printer will error. We don't
+ # want to fail the test in this case--the printer itself
+ # is probably fine, or at least we can't tell.
+ if check_literal.startswith("std::shared_ptr"):
+ shared_ptr = compare_frame.read_var("value")
+ if not "__shared_owners_" in shared_ptr.type.fields():
+ print("IGNORED (no debug info in libc++): " +
+ test_loc.symtab.filename + ":" +
+ str(test_loc.line))
+ return
+
  # Use interactive commands in the correct context to get the pretty
  # printed version