From 699ee6c17aede6561cfb8ba8860fbf362f851e46 Mon Sep 17 00:00:00 2001 From: Pavel Labath Date: Mon, 5 May 2025 16:58:16 +0200 Subject: [PATCH] [lldb/docs] Fix/improve the gdb command map for dynamic types The setting and option value names were wrong. I'm assuming this changed over time, but I haven't tried to figure out when. --- lldb/docs/use/map.rst | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/lldb/docs/use/map.rst b/lldb/docs/use/map.rst index ed285b2d1f6e9..c648b212006e0 100644 --- a/lldb/docs/use/map.rst +++ b/lldb/docs/use/map.rst @@ -800,16 +800,24 @@ Print the dynamic type of the result of an expression (gdb) p someCPPObjectPtrOrReference (Only works for C++ objects) +LLDB does this automatically if determining the dynamic type does not require +running the target (in C++, running the target is never needed). This default is +controlled by the `target.prefer-dynamic-value` setting. If that is disabled, it +can be re-enabled on a per-command basis: + .. code-block:: shell - (lldb) expr -d 1 -- [SomeClass returnAnObject] - (lldb) expr -d 1 -- someCPPObjectPtrOrReference + (lldb) settings set target.prefer-dynamic-value no-dynamic-values + (lldb) frame variable -d no-run-target someCPPObjectPtrOrReference + (lldb) expr -d no-run-target -- someCPPObjectPtr -or set dynamic type printing to be the default: +Note that printing of the dynamic type of references is not possible with the +`expr` command. The workaround is to take the address of the reference and +instruct lldb to print the children of the resulting pointer. .. code-block:: shell - (lldb) settings set target.prefer-dynamic run-target + (lldb) expr -P1 -d no-run-target -- &someCPPObjectReference Call a function so you can stop at a breakpoint in it ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~