Merge commit 'f0a687d821c1' from llvm.org/release/17.x into stable/20230725

Author: git apple-llvm automerger

lld/COFF/InputFiles.cpp

@@ -661,6 +661,8 @@ std::optional<Symbol *> ObjFile::createDefined(
     if (prevailing) {
       SectionChunk *c = readSection(sectionNumber, def, getName());
       sparseChunks[sectionNumber] = c;
+      if (!c)
+        return nullptr;
       c->sym = cast<DefinedRegular>(leader);
       c->selection = selection;
       cast<DefinedRegular>(leader)->data = &c->repl;

lld/test/COFF/comdat-drectve.s

@@ -0,0 +1,31 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -triple=x86_64-windows-gnu %s -filetype=obj -o %t.obj
+
+# RUN: lld-link %t.obj -out:%t.exe -debug:symtab -subsystem:console
+# RUN: llvm-readobj --coff-exports %t.exe | FileCheck %s
+
+# CHECK: Name: exportedFunc
+
+## This assembly snippet has been reduced from what Clang generates from
+## this C snippet, with -fsanitize=address. Normally, the .drectve
+## section would be a regular section - but when compiled with
+## -fsanitize=address, it becomes a comdat section.
+##
+# void exportedFunc(void) {}
+# void mainCRTStartup(void) {}
+# static __attribute__((section(".drectve"), used)) const char export_chkstk[] =
+#     "-export:exportedFunc";
+
+	.text
+	.globl	exportedFunc
+exportedFunc:
+	retq
+
+	.globl	mainCRTStartup
+mainCRTStartup:
+	retq
+
+	.section	.drectve,"dr",one_only,export_chkstk
+export_chkstk:
+	.asciz	"-export:exportedFunc"