[lld-macho][nfc] Test that we don't emit undef symbol errors for dead code

[int3]

Summary

This is what ld64 does too, so we have parity here (though I think ld64
still removes dead code more effectively than we do...)

[thakis]

lg

[thakis]

lld/test/MachO/treat-undef-sym.s

61

(maybe add a new undef symbol and a new _dead symbol in addition to the current one? testing having undefs ref'd by live code seems useful too.)

[int3]

lld/test/MachO/treat-undef-sym.s

61

good idea :)

[thakis]

This breaks tests: http://45.33.8.238/linux/59085/step_11.txt

PTAL :)

[oontvoo]

In D112485#3086095, @thakis wrote:

This breaks tests: http://45.33.8.238/linux/59085/step_11.txt

PTAL :)

Seemed to be fixed by https://github.com/llvm/llvm-project/commit/d3ddd569eb78ae4e042502775704bd27c0c0a543

[dyung]

In D112485#3086100, @oontvoo wrote:

In D112485#3086095, @thakis wrote:

This breaks tests: http://45.33.8.238/linux/59085/step_11.txt

PTAL :)

Seemed to be fixed by https://github.com/llvm/llvm-project/commit/d3ddd569eb78ae4e042502775704bd27c0c0a543

The PS4 linux build bot is still failing after that fix:
https://lab.llvm.org/buildbot/#/builders/139/builds/12148

Command Output (stderr):
--
split-file: error: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/lld/test/MachO/treat-undef-sym.s: No such file or directory
--

[oontvoo]

In D112485#3086130, @dyung wrote:

In D112485#3086100, @oontvoo wrote:

In D112485#3086095, @thakis wrote:

This breaks tests: http://45.33.8.238/linux/59085/step_11.txt

PTAL :)

Seemed to be fixed by https://github.com/llvm/llvm-project/commit/d3ddd569eb78ae4e042502775704bd27c0c0a543

The PS4 linux build bot is still failing after that fix:
https://lab.llvm.org/buildbot/#/builders/139/builds/12148

Command Output (stderr):
--
split-file: error: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/lld/test/MachO/treat-undef-sym.s: No such file or directory
--

Oh, I think int3 should have rm %t and not %s!
should be fixed with https://github.com/llvm/llvm-project/commit/46ef187dccd3be85d0490cf3e5dc73607a4a2ef2 now

[dyung]

In D112485#3086138, @oontvoo wrote:

In D112485#3086130, @dyung wrote:

In D112485#3086100, @oontvoo wrote:

In D112485#3086095, @thakis wrote:

This breaks tests: http://45.33.8.238/linux/59085/step_11.txt

PTAL :)

Seemed to be fixed by https://github.com/llvm/llvm-project/commit/d3ddd569eb78ae4e042502775704bd27c0c0a543

The PS4 linux build bot is still failing after that fix:
https://lab.llvm.org/buildbot/#/builders/139/builds/12148

Command Output (stderr):
--
split-file: error: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/lld/test/MachO/treat-undef-sym.s: No such file or directory
--

Oh, I think int3 should have rm %t and not %s!
should be fixed with https://github.com/llvm/llvm-project/commit/46ef187dccd3be85d0490cf3e5dc73607a4a2ef2 now

Still failing I'm afraid :(

https://lab.llvm.org/buildbot/#/builders/139/builds/12149

Command Output (stderr):
--
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/lld/test/MachO/treat-undef-sym.s:40:10: error: ERROR: expected string not found in input
# ERROR: error: undefined symbol: _bar
         ^
<stdin>:1:1: note: scanning from here
ld64.lld: error: cannot open /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/lld/test/MachO/Output/treat-undef-sym.s.tmp/dead.o: No such file or directory
^
<stdin>:1:11: note: possible intended match here
ld64.lld: error: cannot open /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/lld/test/MachO/Output/treat-undef-sym.s.tmp/dead.o: No such file or directory
          ^
Input file: <stdin>
Check file: /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/lld/test/MachO/treat-undef-sym.s
-dump-input=help explains the following input dump.
Input was:
<<<<<<
            1: ld64.lld: error: cannot open /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/lld/test/MachO/Output/treat-undef-sym.s.tmp/dead.o: No such file or directory 
check:40'0     X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
check:40'1               ?                                                                                                                                                                            possible intended match
>>>>>>
--

[oontvoo]

In D112485#3086139, @dyung wrote:

Still failing I'm afraid :(

How abt now? (I've tested it locally - Linux and OSX)
(after rG46ef187dccd3be85d0490cf3e5dc73607a4a2ef2)

lld/test/MachO/treat-undef-sym.s

 # REQUIRES: x86
+# RUN: split-file %s %t
 
-# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos %s -o %t.o
-# RUN: not %lld -undefined bogus -o /dev/null %t.o 2>&1 | \
+# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos %s -o %t/live.o
+# RUN: not %lld -undefined bogus -o /dev/null %t/live.o 2>&1 | \
 # RUN:     FileCheck %s -check-prefix=UNKNOWN
-# RUN: not %lld -undefined error -o /dev/null %t.o 2>&1 | \
+# RUN: not %lld -undefined error -o /dev/null %t/live.o 2>&1 | \
 # RUN:     FileCheck %s -check-prefix=ERROR
 
-# RUN: not %lld -undefined warning -o /dev/null %t.o 2>&1 | \
+# RUN: not %lld -undefined warning -o /dev/null %t/live.o 2>&1 | \
 # RUN:     FileCheck %s -check-prefix=INVAL-WARNING
-# RUN: not %lld -undefined suppress -o /dev/null %t.o 2>&1 | \
+# RUN: not %lld -undefined suppress -o /dev/null %t/live.o 2>&1 | \
 # RUN:     FileCheck %s -check-prefix=INVAL-SUPPRESS
-# RUN: %lld -undefined dynamic_lookup -lSystem -o %t.out %t.o 2>&1 | count 0
-# RUN: llvm-objdump --macho --lazy-bind %t.out \
+# RUN: %lld -undefined dynamic_lookup -lSystem -o %t/live.out %t/live.o 2>&1 | count 0
+# RUN: llvm-objdump --macho --lazy-bind %t/live.out \
 # RUN:     | FileCheck --check-prefix=BIND %s
 
 # RUN: %no_fatal_warnings_lld -lSystem -flat_namespace -undefined warning \
-# RUN:     -o %t.out %t.o 2>&1 | \
+# RUN:     -o %t/live.out %t/live.o 2>&1 | \
 # RUN:     FileCheck %s -check-prefix=WARNING
-# RUN: llvm-objdump --macho --lazy-bind %t.out \
+# RUN: llvm-objdump --macho --lazy-bind %t/live.out \
 # RUN:     | FileCheck --check-prefix=BIND %s
-# RUN: %lld -flat_namespace -lSystem -undefined suppress -o %t.out %t.o 2>&1 | count 0
-# RUN: llvm-objdump --macho --lazy-bind %t.out \
+# RUN: %lld -flat_namespace -lSystem -undefined suppress -o %t/live.out %t/live.o \
+# RUN:     2>&1 | count 0
+# RUN: llvm-objdump --macho --lazy-bind %t/live.out \
 # RUN:     | FileCheck --check-prefix=BIND %s
-# RUN: %lld -flat_namespace -lSystem -undefined dynamic_lookup -o %t.out %t.o 2>&1 | count 0
-# RUN: llvm-objdump --macho --lazy-bind %t.out \
+# RUN: %lld -flat_namespace -lSystem -undefined dynamic_lookup -o \
+# RUN:     %t/live.out %t/live.o 2>&1 | count 0
+# RUN: llvm-objdump --macho --lazy-bind %t/live.out \
 # RUN:     | FileCheck --check-prefix=BIND %s
 
+## Undefined symbols in dead code should not raise an error iff
+## -dead_strip is enabled.
+# RUN: not %lld -dylib -undefined error -o /dev/null %t/dead.o 2>&1 \
+# RUN:     | FileCheck --check-prefix=ERROR %s
+# RUN: not %lld -dylib -dead_strip -undefined error -o /dev/null %t/live.o 2>&1\
+# RUN:     | FileCheck --check-prefix=ERROR %s
+# RUN: %lld -dylib -dead_strip -undefined error -o /dev/null %t/dead.o
+
 # ERROR: error: undefined symbol: _bar
 # ERROR-NEXT: >>> referenced by
 
 # INVAL-WARNING: error: '-undefined warning' only valid with '-flat_namespace'
 # INVAL-WARNING-NEXT: error: undefined symbol: _bar
 
 # INVAL-SUPPRESS: error: '-undefined suppress' only valid with '-flat_namespace'
 # INVAL-SUPPRESS-NEXT: error: undefined symbol: _bar
 
 # WARNING: warning: undefined symbol: _bar
 # WARNING-NEXT: >>> referenced by
 
 # UNKNOWN: unknown -undefined TREATMENT 'bogus'
 # UNKNOWN-NEXT: error: undefined symbol: _bar
 # UNKNOWN-NEXT: >>> referenced by
 
 # BIND: Lazy bind table:
 # BIND: __DATA   __la_symbol_ptr    0x{{[0-9a-f]*}} flat-namespace   _bar
 
+#--- live.s
 .globl _main
 _main:
   callq _bar
   ret
+
+#--- dead.s
+_dead:
+  callq _bar
+  ret