[lld] 441410b - [ELF] Avoid false-positive assert in getErrPlace()

[Alex Richardson via llvm-commits]

Author: Alex Richardson
Date: 2020-01-15T14:32:25Z
New Revision: 441410be471d5d0a5d1d47cf363de155e397a0c2

URL: https://github.com/llvm/llvm-project/commit/441410be471d5d0a5d1d47cf363de155e397a0c2
DIFF: https://github.com/llvm/llvm-project/commit/441410be471d5d0a5d1d47cf363de155e397a0c2.diff

LOG: [ELF] Avoid false-positive assert in getErrPlace()

This assertion was added as part of D70659 but did not account for .bss
input sections. I noticed that this assert was incorrectly triggering
while building FreeBSD for MIPS64. Fixed by relaxing the assert to also
account for SHT_NOBITS input sections and adjust the test
mips-jalr-non-function.s to link a file with a .bss section first.

Reviewed By: MaskRay, grimar
Differential Revision: https://reviews.llvm.org/D72567

Added: 
    

Modified: 
    lld/ELF/Target.cpp
    lld/test/ELF/mips-jalr-non-functions.s

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp
index 70a68fd8db9e..d3899d0f18f1 100644
--- a/lld/ELF/Target.cpp
+++ b/lld/ELF/Target.cpp
@@ -95,7 +95,7 @@ template <class ELFT> static ErrorPlace getErrPlace(const uint8_t *loc) {
   assert(loc != nullptr);
   for (InputSectionBase *d : inputSections) {
     auto *isec = cast<InputSection>(d);
-    if (!isec->getParent())
+    if (!isec->getParent() || (isec->type & SHT_NOBITS))
       continue;
 
     const uint8_t *isecLoc =

diff  --git a/lld/test/ELF/mips-jalr-non-functions.s b/lld/test/ELF/mips-jalr-non-functions.s
index cdb60cd39e83..70f899c48f6c 100644
--- a/lld/test/ELF/mips-jalr-non-functions.s
+++ b/lld/test/ELF/mips-jalr-non-functions.s
@@ -6,7 +6,12 @@
 ## relocations to avoid generating binaries that crash when executed.
 
 # RUN: llvm-mc -filetype=obj -triple=mips64-unknown-linux %s -o %t.o
-# RUN: ld.lld -shared %t.o -o %t.so 2>&1 | FileCheck %s -check-prefix WARNING-MESSAGE
+## Link in another object file with a .bss as a regression test:
+## Previously LLD asserted when skipping over .bss sections when determining the
+## location for a warning/error message. By adding another file with a .bss
+## section before the actual %t.o we can reproduce this case.
+# RUN: llvm-mc -filetype=obj -triple=mips64-unknown-linux %S/Inputs/common.s -o %t-common.o
+# RUN: ld.lld -shared %t-common.o %t.o -o %t.so 2>&1 | FileCheck %s -check-prefix WARNING-MESSAGE
 # RUN: llvm-objdump --no-show-raw-insn --no-leading-addr -d %t.so | FileCheck %s
 
 .set	noreorder