in the test suite. While this is not really an interesting tool and option to run
on a Mach-O file to show the symbol table in a generic libObject format
it shouldn’t crash.
The reason for the crash was in MachOObjectFile::getSymbolType() when it was
calling MachOObjectFile::getSymbolSection() without checking its return value
for the error case.
What makes this fix require a fair bit of diffs is that the method getSymbolType() is
in the class ObjectFile defined without an ErrorOr<> so I needed to add that all
the sub classes. And all of the uses needed to be updated and the return value
needed to be checked for the error case.
The MachOObjectFile version of getSymbolType() “can” get an error in trying to
come up with the libObject’s internal SymbolRef::Type when the Mach-O symbol
symbol type is an N_SECT type because the code is trying to select from the
SymbolRef::ST_Data or SymbolRef::ST_Function values for the SymbolRef::Type.
And it needs the Mach-O section to use isData() and isBSS to determine if
it will return SymbolRef::ST_Data.
One other possible fix I considered is to simply return SymbolRef::ST_Other
when MachOObjectFile::getSymbolSection() returned an error. But since in
the past when I did such changes that “ate an error in the libObject code” I
was asked instead to push the error out of the libObject code I chose not
to implement the fix this way.
As currently written both the COFF and ELF versions of getSymbolType()
can’t get an error. But if isReservedSectionNumber() wanted to check for
the two known negative values rather than allowing all negative values or
the code wanted to add the same check as in getSymbolAddress() to use
getSection() and check for the error then these versions of getSymbolType()
could return errors.
At the end of the day the error printed now is the generic “Invalid data was
encountered while parsing the file” for object_error::parse_failed. In the
future when we thread Lang’s new TypedError for recoverable error handling
though libObject this will improve. And where the added // Diagnostic(…
comment is, it would be changed to produce and error message
like “bad section index (42) for symbol at index 8” for this case.
llvm-svn: 264187
Summary:
PE files are stripped by default, and only contain the names of exported
symbols.
The actual reason that we bother to do this override by default is
actually due to a quirk of the way -gline-tables-only is implemented, so
I phrased the check as "if we are symbolizing from dwarf, do the symtab
override".
This fixes lots of Windows ASan tests that I broke in r250582.
Reviewers: samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14594
llvm-svn: 253051
Summary:
This is mostly NFC. It is a first step in cleaning up LLVMSymbolize
library. It removes "ModuleInfo" class which bundles together ObjectFile
and its debug info context in favor of:
* abstract SymbolizableModule in public headers;
* SymbolizableObjectFile subclass in implementation.
Additionally, SymbolizableObjectFile is now created via factory, so we
can properly detect object parsing error at this stage instead of keeping
the broken half-parsed object. As a next step, we would be able to
propagate the error all the way back to the library user.
Further improvements might include:
* factoring out the logic of finding appropriate file with debug info
for a given object file, and caching all parsed object files into a
separate class [A].
* factoring out DILineInfo rendering [B].
This would make what is now a heavyweight "LLVMSymbolizer" a relatively
straightforward class, that calls into [A] to turn filepath into a
SymbolizableModule, delegates actual symbolization to concrete SymbolizableModule
implementation, and lets [C] render the result.
Reviewers: dblaikie, echristo, rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14099
llvm-svn: 251662
Kevin Enderby