[LLD] Report errors occurred while parsing debug info as warnings.

Summary:
Extracted from D74773. Currently, errors happened while parsing
debug info are reported as errors. DebugInfoDWARF library treats such
errors as "Recoverable errors". This patch makes debug info errors
to be reported as warnings, to support DebugInfoDWARF approach.

Reviewers: ruiu, grimar, MaskRay, jhenderson, espindola

Reviewed By: MaskRay, jhenderson

Subscribers: emaste, aprantl, arichardson, arphaman, llvm-commits

Tags: #llvm, #debug-info, #lld

Differential Revision: https://reviews.llvm.org/D75234

Author: avl-llvm

lld/ELF/SyntheticSections.cpp

@@ -2668,12 +2668,12 @@ readAddressAreas(DWARFContext &dwarf, InputSection *sec) {
   uint32_t cuIdx = 0;
   for (std::unique_ptr<DWARFUnit> &cu : dwarf.compile_units()) {
     if (Error e = cu->tryExtractDIEsIfNeeded(false)) {
-      error(toString(sec) + ": " + toString(std::move(e)));
+      warn(toString(sec) + ": " + toString(std::move(e)));
       return {};
     }
     Expected<DWARFAddressRangesVector> ranges = cu->collectAddressRanges();
     if (!ranges) {
-      error(toString(sec) + ": " + toString(ranges.takeError()));
+      warn(toString(sec) + ": " + toString(ranges.takeError()));
       return {};
     }
 

lld/test/ELF/gdb-index-invalid-ranges.s

@@ -1,12 +1,12 @@
 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
-# RUN: not ld.lld --gdb-index -e main %t.o -o /dev/null 2>&1 | FileCheck %s
+# RUN: ld.lld --gdb-index -e main %t.o -o /dev/null 2>&1 | FileCheck %s
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %p/Inputs/gdb-index-invalid-ranges.obj.s -o %t2.o
 # RUN: llvm-ar rc %t.a %t.o
-# RUN: not ld.lld --gdb-index -e main %t2.o %t.a -o /dev/null 2>&1 | FileCheck --check-prefix=ARCHIVE %s
+# RUN: ld.lld --gdb-index -e main %t2.o %t.a -o /dev/null 2>&1 | FileCheck --check-prefix=ARCHIVE %s
 
-# CHECK: ld.lld: error: {{.*}}gdb-index-invalid-ranges.s.tmp.o:(.debug_info): decoding address ranges: invalid range list entry at offset 0x10
-# ARCHIVE: ld.lld: error: {{.*}}gdb-index-invalid-ranges.s.tmp.a(gdb-index-invalid-ranges.s.tmp.o):(.debug_info): decoding address ranges: invalid range list entry at offset 0x10
+# CHECK: ld.lld: warning: {{.*}}gdb-index-invalid-ranges.s.tmp.o:(.debug_info): decoding address ranges: invalid range list entry at offset 0x10
+# ARCHIVE: ld.lld: warning: {{.*}}gdb-index-invalid-ranges.s.tmp.a(gdb-index-invalid-ranges.s.tmp.o):(.debug_info): decoding address ranges: invalid range list entry at offset 0x10
 
 .section .text.foo1,"ax",@progbits
 .globl f1

lld/test/ELF/gdb-index-parse-fail.s

@@ -1,8 +1,8 @@
 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t1.o
-# RUN: not ld.lld --gdb-index %t1.o -o /dev/null 2>&1 | FileCheck %s
+# RUN: ld.lld --gdb-index %t1.o -o /dev/null 2>&1 | FileCheck %s
 
-# CHECK: error: {{.*}}:(.debug_info): invalid reference to or invalid content in .debug_str_offsets[.dwo]: insufficient space for 32 bit header prefix
+# CHECK: warning: {{.*}}:(.debug_info): invalid reference to or invalid content in .debug_str_offsets[.dwo]: insufficient space for 32 bit header prefix
 
 .section .debug_abbrev,"",@progbits
   .byte  1                           # Abbreviation Code