[llvm-readelf/readobj] - Fix the behavior when a sections is included…

… in two groups at the same time.

The current behavior was introduced by me in D37567 and it is a bit strange. It prints the
"Error: ...." message to the errs() manually and stops dumping the group section which has this error.
This behavior is consistent with GNU though, but it is very inconsistent with what the regular llvm-readelf
code usually does/prints, so I suggest to change the implementation:

1) Instead of printing "Error: ...." to errs() - just report a warning.
2) Try to continue dumping the section.
3) Merge broken-group.test to group.text.

This is what this patch does.

Differential revision: https://reviews.llvm.org/D84170

llvm/test/tools/llvm-readobj/ELF/groups.test

@@ -61,7 +61,7 @@ Sections:
     Info: bar
     Members:
       - SectionOrType: GRP_COMDAT
-      - SectionOrType: .text.bar
+      - SectionOrType: [[TEXTBARNAME=.text.bar]]
       - SectionOrType: .rela.text.bar
   - Name:  .text.foo
     Type:  SHT_PROGBITS
@@ -80,3 +80,47 @@ Symbols:
     Section: .text.foo
   - Name:    bar
     Section: .text.bar
+
+## Check that we report a warning and continue dumping when a section is included
+## in two group sections at the same time.
+
+# RUN: yaml2obj %s -DTEXTBARNAME=.text.foo -o %t.dup.o
+# RUN: llvm-readobj --elf-section-groups %t.dup.o 2>&1 | FileCheck %s -DFILE=%t.dup.o --check-prefix=DUP-LLVM
+# RUN: llvm-readelf --elf-section-groups %t.dup.o 2>&1 | FileCheck %s -DFILE=%t.dup.o --check-prefix=DUP-GNU
+
+# DUP-LLVM:      Group {
+# DUP-LLVM-NEXT:   Name: .group
+# DUP-LLVM-NEXT:   Index: 1
+# DUP-LLVM-NEXT:   Link: 7
+# DUP-LLVM-NEXT:   Info: 1
+# DUP-LLVM-NEXT:   Type: COMDAT
+# DUP-LLVM-NEXT:   Signature: foo
+# DUP-LLVM-NEXT:   Section(s) in group [
+# DUP-LLVM-NEXT:     .text.foo (3)
+# DUP-LLVM-NEXT:     .rela.text.foo (4)
+# DUP-LLVM-NEXT:   ]
+# DUP-LLVM-NEXT: }
+# DUP-LLVM:      Group {
+# DUP-LLVM-NEXT:   Name: .group1
+# DUP-LLVM-NEXT:   Index: 2
+# DUP-LLVM-NEXT:   Link: 7
+# DUP-LLVM-NEXT:   Info: 2
+# DUP-LLVM-NEXT:   Type: COMDAT
+# DUP-LLVM-NEXT:   Signature: bar
+# DUP-LLVM-NEXT:   Section(s) in group [
+# DUP-LLVM-NEXT: warning: '[[FILE]]': section with index 3, included in the group section with index 1, was also found in the group section with index 2
+# DUP-LLVM-NEXT:     .text.foo (3)
+# DUP-LLVM-NEXT:     .rela.text.bar (6)
+# DUP-LLVM-NEXT:   ]
+# DUP-LLVM-NEXT: }
+
+# DUP-GNU:      COMDAT group section [    1] `.group' [foo] contains 2 sections:
+# DUP-GNU-NEXT:  [Index]    Name
+# DUP-GNU-NEXT:  [    3]   .text.foo
+# DUP-GNU-NEXT:  [    4]   .rela.text.foo
+
+# DUP-GNU:      COMDAT group section [    2] `.group1' [bar] contains 2 sections:
+# DUP-GNU-NEXT:    [Index]    Name
+# DUP-GNU-NEXT: warning: '[[FILE]]': section with index 3, included in the group section with index 1, was also found in the group section with index 2
+# DUP-GNU-NEXT:    [    3]   .text.foo
+# DUP-GNU-NEXT:    [    6]   .rela.text.bar

llvm/tools/llvm-readobj/ELFDumper.cpp

@@ -3605,15 +3605,13 @@ template <class ELFT> void GNUStyle<ELFT>::printGroupSections(const ELFO *Obj) {
        << "   [Index]    Name\n";
     for (const GroupMember &GM : G.Members) {
       const GroupSection *MainGroup = Map[GM.Index];
-      if (MainGroup != &G) {
-        OS.flush();
-        errs() << "Error: section [" << format_decimal(GM.Index, 5)
-               << "] in group section [" << format_decimal(G.Index, 5)
-               << "] already in group section ["
-               << format_decimal(MainGroup->Index, 5) << "]";
-        errs().flush();
-        continue;
-      }
+      if (MainGroup != &G)
+        this->reportUniqueWarning(
+            createError("section with index " + Twine(GM.Index) +
+                        ", included in the group section with index " +
+                        Twine(MainGroup->Index) +
+                        ", was also found in the group section with index " +
+                        Twine(G.Index)));
       OS << "   [" << format_decimal(GM.Index, 5) << "]   " << GM.Name << "\n";
     }
   }
@@ -6197,15 +6195,13 @@ void LLVMStyle<ELFT>::printGroupSections(const ELFO *Obj) {
     ListScope L(W, "Section(s) in group");
     for (const GroupMember &GM : G.Members) {
       const GroupSection *MainGroup = Map[GM.Index];
-      if (MainGroup != &G) {
-        W.flush();
-        errs() << "Error: " << GM.Name << " (" << GM.Index
-               << ") in a group " + G.Name + " (" << G.Index
-               << ") is already in a group " + MainGroup->Name + " ("
-               << MainGroup->Index << ")\n";
-        errs().flush();
-        continue;
-      }
+      if (MainGroup != &G)
+        this->reportUniqueWarning(
+            createError("section with index " + Twine(GM.Index) +
+                        ", included in the group section with index " +
+                        Twine(MainGroup->Index) +
+                        ", was also found in the group section with index " +
+                        Twine(G.Index)));
       W.startLine() << GM.Name << " (" << GM.Index << ")\n";
     }
   }