tools: fix invalid printing, buffer overrun in llvm-readobj

All auxiliary records are consumed when accessing a File record.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206354 91177308-0d34-0410-b5e6-96231b3b80d8

test/tools/llvm-readobj/Inputs/file-multiple-aux-records.yaml

@@ -0,0 +1,21 @@
+header: !Header
+  Machine: IMAGE_FILE_MACHINE_I386 # (0x14c)
+  Characteristics: [ IMAGE_FILE_DEBUG_STRIPPED ]
+sections:
+symbols:
+  - !Symbol
+    Name: .file
+    Value: 0
+    SectionNumber: 65534
+    SimpleType: IMAGE_SYM_TYPE_NULL
+    ComplexType: IMAGE_SYM_DTYPE_NULL
+    StorageClass: IMAGE_SYM_CLASS_FILE
+    File: first-section-has-eighteen-characters.asm
+  - !Symbol
+    Name: '@comp.id'
+    Value: 13485607
+    SectionNumber: 65535
+    SimpleType: IMAGE_SYM_TYPE_NULL
+    ComplexType: IMAGE_SYM_DTYPE_NULL
+    StorageClass: IMAGE_SYM_CLASS_STATIC
+

test/tools/llvm-readobj/coff-file-sections-reading.test

@@ -0,0 +1,18 @@
+RUN: yaml2obj %p/Inputs/file-multiple-aux-records.yaml | llvm-readobj -t - | FileCheck %s
+
+CHECK: Symbols [
+CHECK:   Symbol {
+CHECK:     Name: .file
+CHECK:     Value: 0
+CHECK:     Section:  (65534)
+CHECK:     BaseType: Null (0x0)
+CHECK:     ComplexType: Null (0x0)
+CHECK:     StorageClass: File (0x67)
+CHECK:     AuxSymbolCount: 3
+CHECK:     AuxFileRecord {
+CHECK:       FileName: first-section-has-eighteen-characters.asm
+CHECK:     }
+CHECK-NOT:     AuxFileRecord {
+CHECK:   }
+CHECK: ]
+

tools/llvm-readobj/COFFDumper.cpp

@@ -981,6 +981,7 @@ void COFFDumper::printSymbol(const SymbolRef &Sym) {
       StringRef Name(Aux->FileName,
                      Symbol->NumberOfAuxSymbols * COFF::SymbolSize);
       W.printString("FileName", Name.rtrim(StringRef("\0", 1)));
+      break;
     } else if (Symbol->isSectionDefinition()) {
       const coff_aux_section_definition *Aux;
       if (error(getSymbolAuxData(Obj, Symbol + I, Aux)))