Add an interesting test case we already pass.

We had no tests for the interaction of relocations pointing to tail
merged strings.

llvm-svn: 265853

lld/test/ELF/merge-shared-str.s

@@ -0,0 +1,28 @@
+// REQUIRES: x86
+// RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+// RUN: ld.lld %t.o -o %t.so -shared -O3
+// RUN: llvm-readobj -r -s %t.so | FileCheck %s
+
+
+        .section        foo,"aMS",@progbits,1
+        .asciz "bar"
+        .asciz "ar"
+
+        .text
+        .quad foo + 4
+
+
+// CHECK:      Name: foo
+// CHECK-NEXT: Type: SHT_PROGBITS
+// CHECK-NEXT: Flags [
+// CHECK-NEXT:   SHF_ALLOC
+// CHECK-NEXT:   SHF_MERGE
+// CHECK-NEXT:   SHF_STRINGS
+// CHECK-NEXT: ]
+// CHECK-NEXT: Address: 0x1C8
+
+// CHECK:      Relocations [
+// CHECK-NEXT:   Section ({{.*}}) .rela.dyn {
+// CHECK-NEXT:     0x{{.*}} R_X86_64_RELATIVE - 0x1C9
+// CHECK-NEXT:   }
+// CHECK-NEXT: ]