Fix --start-group/end-group.

We used to manage the state whether we are in a group or not
using a counter. The counter is incremented by one if we jump from
end-group to start-group, and decremented by one if we don't.
The counter was assumed to be either zero or one, but obviously it
could be negative (if there's a group which is not repeated at all).
This is a fix for that issue.

llvm-svn: 226632

3 files changed, 15 insertions, 9 deletions

diff --git a/lld/include/lld/Core/Resolver.h b/lld/include/lld/Core/Resolver.h
index 63ed68b2561..0e827bee953 100644
--- a/lld/include/lld/Core/Resolver.h
+++ b/lld/include/lld/Core/Resolver.h
@@ -58,7 +58,7 @@ private:
   typedef std::function<void(StringRef, bool)> UndefCallback;
 
   bool undefinesAdded(int begin, int end);
-  File *getFile(int &index, int &groupLevel);
+  File *getFile(int &index, bool &inGroup);
 
   /// \brief Add section group/.gnu.linkonce if it does not exist previously.
   void maybeAddSectionGroupOrGnuLinkOnce(const DefinedAtom &atom);
diff --git a/lld/lib/Core/Resolver.cpp b/lld/lib/Core/Resolver.cpp
index 79432bebb84..2fcd254aa68 100644
--- a/lld/lib/Core/Resolver.cpp
+++ b/lld/lib/Core/Resolver.cpp
@@ -254,7 +254,7 @@ bool Resolver::undefinesAdded(int begin, int end) {
   return false;
 }
 
-File *Resolver::getFile(int &index, int &groupLevel) {
+File *Resolver::getFile(int &index, bool &inGroup) {
   std::vector<std::unique_ptr<Node>> &inputs = _context.getNodes();
   if ((size_t)index >= inputs.size())
     return nullptr;
@@ -265,12 +265,12 @@ File *Resolver::getFile(int &index, int &groupLevel) {
     int size = group->getSize();
     if (undefinesAdded(index - size, index)) {
       index -= size;
-      ++groupLevel;
-      return getFile(index, groupLevel);
+      inGroup = true;
+      return getFile(index, inGroup);
     }
     ++index;
-    --groupLevel;
-    return getFile(index, groupLevel);
+    inGroup = false;
+    return getFile(index, inGroup);
   }
   return cast<FileNode>(inputs[index++].get())->getFile();
 }
@@ -290,10 +290,10 @@ void Resolver::makePreloadArchiveMap() {
 bool Resolver::resolveUndefines() {
   ScopedTask task(getDefaultDomain(), "resolveUndefines");
   int index = 0;
-  int groupLevel = 0;
+  bool inGroup = false;
   for (;;) {
     bool undefAdded = false;
-    File *file = getFile(index, groupLevel);
+    File *file = getFile(index, inGroup);
     if (!file)
       return true;
     if (std::error_code ec = file->parse()) {
@@ -304,7 +304,7 @@ bool Resolver::resolveUndefines() {
     file->beforeLink();
     switch (file->kind()) {
     case File::kindObject:
-      if (groupLevel > 0)
+      if (inGroup)
         break;
       assert(!file->hasOrdinal());
       file->setOrdinal(_context.getNextOrdinalAndIncrement());
diff --git a/lld/test/pecoff/Inputs/vars-main-x86.obj.yaml b/lld/test/pecoff/Inputs/vars-main-x86.obj.yaml
index 4bee575ddf4..fb016828df9 100644
--- a/lld/test/pecoff/Inputs/vars-main-x86.obj.yaml
+++ b/lld/test/pecoff/Inputs/vars-main-x86.obj.yaml
@@ -60,4 +60,10 @@ symbols:
     SimpleType:      IMAGE_SYM_TYPE_NULL
     ComplexType:     IMAGE_SYM_DTYPE_NULL
     StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            ___ImageBase
+    Value:           0
+    SectionNumber:   0
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
 ...