Author: David Spickett Date: 2025-05-28T16:29:48+01:00 New Revision: 0ac3f5e9017b9072d80038957f41991c8a3b195c
URL: https://github.com/llvm/llvm-project/commit/0ac3f5e9017b9072d80038957f41991c8a3b195c DIFF: https://github.com/llvm/llvm-project/commit/0ac3f5e9017b9072d80038957f41991c8a3b195c.diff LOG: [lldb][test] Fix flaky DIL array subscript test by reducing array indexes (#141738) This test has been flaky on Linaro's Windows on Arm bot and I was able to reproduce it within 10 or so runs locally. When it fails it's because we failed to read the value of int_arr[100]. When that happens the memory looks like this: ``` [0x0000006bf88fd000-0x0000006bf8900000) rw- <-- sp (0x0000006bf88ffe20) [0x0000006bf8900000-0x0000025fec900000) --- <-- int_arr[100] (0x0000006bf8900070) ``` The first region is the stack and the stack pointer is pointing within that region, as expected. The second region is where we are trying to read int_arr[100] from and this is not mapped because we're trying to read above the start of the stack. Sometimes the test passes I think because ASLR / DYNAMICBASE moves the start of the stack down enough so there is some readable memory at the top. https://learn.microsoft.com/en-us/cpp/build/reference/dynamicbase?view=msvc-170 Note "Because ASLR can't be disabled on ARM, ARM64, or ARM64EC architectures, /DYNAMICBASE:NO isn't supported for these targets.". Which means on this bot, the layout is definitely being randomised. We don't need to be testing indexes this large. So I've changed the two test indexes to 3 (1 beyond the end) and 10 (a larger distance beyond the end). We know that index 42 always worked on the bot, so 10 should be fine, and did not fail locally. Added: Modified: lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py Removed: ################################################################################ diff --git a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py index 66f4c62761004..0d91f804ce565 100644 --- a/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py +++ b/lldb/test/API/commands/frame/var-dil/basics/ArraySubscript/TestFrameVarDILArraySubscript.py @@ -19,8 +19,6 @@ def expect_var_path(self, expr, compare_to_framevar=False, value=None, type=None self.runCmd("settings set target.experimental.use-DIL true") self.assertEqual(value_dil.GetValue(), value_frv.GetValue()) - # int_arr[100] sometimes points to above the stack region, fix coming soon. - @skipIfWindows def test_subscript(self): self.build() lldbutil.run_to_source_breakpoint( @@ -53,9 +51,10 @@ def test_subscript(self): # Both typedefs and refs self.expect("frame var 'td_int_arr_ref[td_int_idx_1_ref]'", error=True) - # Test for index out of bounds. - self.expect_var_path("int_arr[42]", True, type="int") - self.expect_var_path("int_arr[100]", True, type="int") + # Test for index out of bounds. 1 beyond the end. + self.expect_var_path("int_arr[3]", True, type="int") + # Far beyond the end (but not far enough to be off the top of the stack). + self.expect_var_path("int_arr[10]", True, type="int") # Test address-of of the subscripted value. self.expect_var_path("*(&int_arr[1])", value="2") _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
