[lld] 34b14cc - [lld][ELF] Suppress `--orphan-handling=error/warn` without `SECTIONS` (#93630)

[via llvm-commits]

Author: Igor Kudrin
Date: 2024-05-29T14:53:29-07:00
New Revision: 34b14cc4f88b5e3d757f2ab20c19387178056567

URL: https://github.com/llvm/llvm-project/commit/34b14cc4f88b5e3d757f2ab20c19387178056567
DIFF: https://github.com/llvm/llvm-project/commit/34b14cc4f88b5e3d757f2ab20c19387178056567.diff

LOG: [lld][ELF] Suppress `--orphan-handling=error/warn` without `SECTIONS` (#93630)

Without a linker script, `--orphan-handling=error` or `=warn` reports
all input sections, including even well-known sections like `.text`,
`.bss`, `.dynamic`, or `.symtab`. However, in this case, no sections
should be considered orphans because they all are placed with the same
default rules. This patch suppresses errors/warnings for placing orphan
sections if no linker script with the `SECTIONS` command is provided.

The proposed behavior matches GNU gold. GNU ld in the same scenario only
reports sections that are not in its default linker script, thus, it
avoids complaining about `.text` and similar.

Added: 
    

Modified: 
    lld/ELF/LinkerScript.cpp
    lld/test/ELF/linkerscript/orphan-report.s

Removed: 
    


################################################################################
diff  --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index 3ba59c112b8a8..94a39034d629f 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -936,7 +936,8 @@ void LinkerScript::addOrphanSections() {
 
 void LinkerScript::diagnoseOrphanHandling() const {
   llvm::TimeTraceScope timeScope("Diagnose orphan sections");
-  if (config->orphanHandling == OrphanHandlingPolicy::Place)
+  if (config->orphanHandling == OrphanHandlingPolicy::Place ||
+      !hasSectionsCommand)
     return;
   for (const InputSectionBase *sec : orphanSections) {
     // .relro_padding is inserted before DATA_SEGMENT_RELRO_END, if present,

diff  --git a/lld/test/ELF/linkerscript/orphan-report.s b/lld/test/ELF/linkerscript/orphan-report.s
index 3dca23267ec64..eedcc4eff8168 100644
--- a/lld/test/ELF/linkerscript/orphan-report.s
+++ b/lld/test/ELF/linkerscript/orphan-report.s
@@ -11,6 +11,13 @@
 # RUN: ld.lld -shared --orphan-handling=place -o %t.out --script %t.script \
 # RUN:   %t.o 2>&1 -verbose  -error-limit=0 | FileCheck %s --check-prefix=DEFAULT
 
+## Check --orphan-handling=error or =warn do not report errors if no linker
+## script is used.
+# RUN: ld.lld -shared -orphan-handling=error -o /dev/null %t.o 2>&1 | count 0
+# RUN: ld.lld -shared -orphan-handling=warn -o /dev/null %t.o 2>&1 | count 0
+# RUN: ld.lld -r -orphan-handling=error -o /dev/null %t.o 2>&1 | count 0
+# RUN: ld.lld -r -orphan-handling=warn -o /dev/null %t.o 2>&1 | count 0
+
 ## Check --orphan-handling=error reports errors about orphans.
 # RUN: not ld.lld --orphan-handling=error -o /dev/null -T %t.script \
 # RUN:   %t.o 2>&1 | FileCheck %s --check-prefixes=COMMON,SYMTAB