[ELF] - Do not segfault when using --gc-sections with linker script
Patch fixes PR32024.
Sections that were not marked as Live has null output section.
Previously we tried to access that field and segfaulted.
Differential revision: https://reviews.llvm.org/D30188
llvm-svn: 295727
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index db7bb03..a5ecf48 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -503,6 +503,8 @@
continue;
auto *IB = static_cast<InputSectionBase<ELFT> *>(ID);
+ if (!IB->Live)
+ continue;
switchTo(IB->OutSec);
if (auto *I = dyn_cast<InputSection<ELFT>>(IB))
output(I);
diff --git a/lld/test/ELF/linkerscript/sections-gc.s b/lld/test/ELF/linkerscript/sections-gc.s
new file mode 100644
index 0000000..d71dc65
--- /dev/null
+++ b/lld/test/ELF/linkerscript/sections-gc.s
@@ -0,0 +1,19 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: echo "SECTIONS { .text : { *(.text*) } }" > %t.script
+# RUN: ld.lld %t --gc-sections --script %t.script -o %t1
+# RUN: llvm-objdump -section-headers %t1 | FileCheck %s
+
+# CHECK: Sections:
+# CHECK-NEXT: Name Size
+# CHECK: .text 00000001
+
+.section .text.foo, "ax"
+.global _start
+_start:
+ nop
+
+.section .text.bar, "ax"
+.global bar
+bar:
+ nop