lld-link: Store comdat selection in SectionChunk, reject more invalid associated comdats
I need the comdat selection for PR40094. To keep the patch for that smaller,
I'm adding it here, and as a first application I'm using it to reject
associative comdats referring to earlier associative comdats. Depends on
D56929; together with that all associative comdats referring to other
associative comdats are now rejected.
Differential Revision: https://reviews.llvm.org/D56931
git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@352254 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/COFF/Chunks.h b/COFF/Chunks.h
index 0185da1..60dbf1f 100644
--- a/COFF/Chunks.h
+++ b/COFF/Chunks.h
@@ -223,6 +223,9 @@
// The COMDAT leader symbol if this is a COMDAT chunk.
DefinedRegular *Sym = nullptr;
+ // The COMDAT selection if this is a COMDAT chunk.
+ llvm::COFF::COMDATType Selection;
+
ArrayRef<coff_relocation> Relocs;
// Used by the garbage collector.
diff --git a/COFF/InputFiles.cpp b/COFF/InputFiles.cpp
index f291a9d..4b87e02 100644
--- a/COFF/InputFiles.cpp
+++ b/COFF/InputFiles.cpp
@@ -226,10 +226,7 @@
uint32_t ParentIndex) {
SectionChunk *Parent = SparseChunks[ParentIndex];
- if (Parent == PendingComdat) {
- // This can happen if an associative comdat refers to another associative
- // comdat that appears after it (invalid per COFF spec) or to a section
- // without any symbols.
+ auto Diag = [&]() {
StringRef Name, ParentName;
COFFObj->getSymbolName(Sym, Name);
@@ -238,6 +235,13 @@
COFFObj->getSectionName(ParentSec, ParentName);
error(toString(this) + ": associative comdat " + Name +
" has invalid reference to section " + ParentName);
+ };
+
+ if (Parent == PendingComdat) {
+ // This can happen if an associative comdat refers to another associative
+ // comdat that appears after it (invalid per COFF spec) or to a section
+ // without any symbols.
+ Diag();
return;
}
@@ -245,7 +249,14 @@
// the section; otherwise mark it as discarded.
int32_t SectionNumber = Sym.getSectionNumber();
if (Parent) {
- SparseChunks[SectionNumber] = readSection(SectionNumber, Def, "");
+ if (Parent->Selection == IMAGE_COMDAT_SELECT_ASSOCIATIVE) {
+ Diag();
+ return;
+ }
+
+ SectionChunk *C = readSection(SectionNumber, Def, "");
+ C->Selection = IMAGE_COMDAT_SELECT_ASSOCIATIVE;
+ SparseChunks[SectionNumber] = C;
if (SparseChunks[SectionNumber])
Parent->addAssociative(SparseChunks[SectionNumber]);
} else {
diff --git a/test/COFF/associative-comdat-order.test b/test/COFF/associative-comdat-order.test
index 31105d5..09b1b46 100644
--- a/test/COFF/associative-comdat-order.test
+++ b/test/COFF/associative-comdat-order.test
@@ -1,10 +1,16 @@
-# RUN: yaml2obj < %s > %t.obj
-# RUN: not lld-link /include:symbol /dll /noentry /nodefaultlib %t.obj /out:%t.exe 2>&1 | FileCheck %s
-
# Tests that an associative comdat being associated with another
# associated comdat later in the file produces an error.
-# CHECK: lld-link: error: {{.*}}: associative comdat .text$ac1 has invalid reference to section .text$ac2
-# CHECK-NOT: lld-link: error:
+# RUN: sed -e s/ASSOC1/2/ -e s/ASSOC2/3/ %s | yaml2obj > %t.obj
+# RUN: not lld-link /include:symbol /dll /noentry /nodefaultlib %t.obj /out:%t.exe 2>&1 | FileCheck --check-prefix=FORWARD %s
+# FORWARD: lld-link: error: {{.*}}: associative comdat .text$ac1 has invalid reference to section .text$ac2
+# FORWARD-NOT: lld-link: error:
+
+# Tests that an associative comdat being associated with another
+# associated comdat earlier in the file produces an error.
+# RUN: sed -e s/ASSOC1/3/ -e s/ASSOC2/1/ %s | yaml2obj > %t.obj
+# RUN: not lld-link /include:symbol /dll /noentry /nodefaultlib %t.obj /out:%t.exe 2>&1 | FileCheck --check-prefix=BACKWARD %s
+# BACKWARD: lld-link: error: {{.*}}: associative comdat .text$ac2 has invalid reference to section .text$ac1
+# BACKWARD-NOT: lld-link: error:
--- !COFF
header:
@@ -35,7 +41,7 @@
NumberOfRelocations: 0
NumberOfLinenumbers: 0
CheckSum: 3099354981
- Number: 2
+ Number: ASSOC1
Selection: IMAGE_COMDAT_SELECT_ASSOCIATIVE
- Name: '.text$ac2'
Value: 0
@@ -48,7 +54,7 @@
NumberOfRelocations: 0
NumberOfLinenumbers: 0
CheckSum: 3099354981
- Number: 3
+ Number: ASSOC2
Selection: IMAGE_COMDAT_SELECT_ASSOCIATIVE
- Name: '.text$nm'
Value: 0
