maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[dsymutil] Fix handling of aliases to private external symbols 

dsymutil was incorrectly ignoring aliases to private extern symbols in
the MachODebugMapParser. This resulted in spurious warnings about not
being able to find symbols.

rdar://49652389

Differential revision: https://reviews.llvm.org/D89444
This commit is contained in:
Jonas Devlieghere 2020-10-14 20:10:55 -07:00
parent 54c1bcab90
commit f9fb9da36c
5 changed files with 32 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
llvm/test/tools/dsymutil/ARM/private-extern-alias.test Normal file
View File

@ -0,0 +1,29 @@
$ cat private_extern.c
__attribute__((visibility("hidden")))
int* foo() {
int i = 10;
volatile int* j = &i;
return j;
}
int* bar() {
return foo();
}
$ cat main.c
int* bar();
int main() {
return *bar();
}
$ cat alias_list
_foo _baz
$ xcrun --sdk iphoneos clang -g private_extern.c -c -o private_extern.o -target arm64-apple-ios14.0
$ xcrun --sdk iphoneos clang -g main.c -c -o main.o -target arm64-apple-ios14.0
$ xcrun --sdk iphoneos clang private_extern.o main.o -target arm64-apple-ios14.0 -o private_extern.out -Xlinker -alias_list -Xlinker alias_list
RUN: dsymutil -oso-prepend-path %p/../Inputs %p/../Inputs/private/tmp/private_extern/private_extern.out -o %t.dSYM --verbose 2>&1 | FileCheck %s
CHECK-NOT: could not find object file symbol for symbol _baz
CHECK: { sym: _foo, objAddr: 0x0000000000000000, binAddr: 0x0000000100007F58, size: 0x00000020 }
CHECK: { sym: _baz, objAddr: 0x0000000000000000, binAddr: 0x0000000100007F58, size: 0x00000000 }

BIN
llvm/test/tools/dsymutil/Inputs/private/tmp/private_extern/main.o Normal file
View File

Binary file not shown.

BIN
llvm/test/tools/dsymutil/Inputs/private/tmp/private_extern/private_extern.o Normal file
View File

Binary file not shown.

BIN
llvm/test/tools/dsymutil/Inputs/private/tmp/private_extern/private_extern.out Executable file
View File

Binary file not shown.

4
llvm/tools/dsymutil/MachODebugMapParser.cpp
View File

@ -562,7 +562,9 @@ void MachODebugMapParser::loadMainBinarySymbols(
continue;
}
Section = *SectionOrErr;
if (Section == MainBinary.section_end() || Section->isText())
if ((Section == MainBinary.section_end() || Section->isText()) &&
!(SymType &
MachO::N_PEXT)) // Alias to non-external (was a private external)
continue;
uint64_t Addr = cantFail(Sym.getValue());
Expected<StringRef> NameOrErr = Sym.getName();