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[patch] [gdb/testsuite] include a use of the definition of a type to cause clang to emit debug info


Clang has an optimization that causes a the debug info to only include
the declaration of a type if the type is referenced but never used in
a context that requires a definition (eg: pointers are handed around
but never deferenced).

This patch introduces a variable to one test file to cause clang to
emit the full definition of the type as well as fixing up a related
typo in the test message of the associated expect file.

Like the difference between GCC and Clang in the emission of unused
static entities, I think this case is also a matter of degrees - both
GCC and Clang implement other similar optimizations* to the one
outlined here and the GDB test suite has managed to pass without
disabling those optimizations in GCC and I hope it's suitable to do
the same for Clang.

Though admittedly I don't have much of the context of the history of
the testsuite, its priorities/preferences when it comes to
distinguishing testing compiler behavior versus debugger behavior,
etc.

* the one I know of involves dynamic types: both GCC and Clang only
emit the debug info definition of such a type in any translation unit
that emits the key function. This means in many contexts where a full
definition is provided in the source only a declaration is provided in
the debug info.

Attachment: clang_full_type.diff
Description: Text document


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