[Lldb-commits] [lldb] [LLDB][ELF] Fix section unification to not just use names. (PR #90099)

[Alastair Houghton via lldb-commits]

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@@ -1854,6 +1854,49 @@ class VMAddressProvider {
 };
 }
 
+namespace {
+  // We have to do this because ELF doesn't have section IDs, and also
+  // doesn't require section names to be unique.  (We use the section index
+  // for section IDs, but that isn't guaranteed to be the same in separate
+  // debug images.)
+  SectionSP FindMatchingSection(const SectionList &section_list,
+                                SectionSP section) {
+    SectionSP sect_sp;
+
+    addr_t vm_addr = section->GetFileAddress();
+    ConstString name = section->GetName();
+    offset_t file_size = section->GetFileSize();
+    offset_t byte_size = section->GetByteSize();
+    SectionType type = section->GetType();
+    bool thread_specific = section->IsThreadSpecific();
+    uint32_t permissions = section->GetPermissions();
+    uint32_t alignment = section->GetLog2Align();
+
+    for (auto sect_iter = section_list.begin();
+         sect_iter != section_list.end();
+         ++sect_iter) {
+      if ((*sect_iter)->GetName() == name
+          && (*sect_iter)->GetType() == type
+          && (*sect_iter)->IsThreadSpecific() == thread_specific
+          && (*sect_iter)->GetPermissions() == permissions
+          && (*sect_iter)->GetFileSize() == file_size
+          && (*sect_iter)->GetByteSize() == byte_size
+          && (*sect_iter)->GetFileAddress() == vm_addr
+          && (*sect_iter)->GetLog2Align() == alignment) {
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al45tair wrote:

I didn't want to do that, because I didn't want to give the impression that this was a general purpose way to compare two `Section`s. While it checks _many_ of the section attributes, it doesn't check all of them (intentionally in the case of which object they come from), and I think that would be surprising behaviour from an `==` operator.

https://github.com/llvm/llvm-project/pull/90099