[ELF] - Fix cref.s test case.

The intention of -gc-sections flag was to check
that discarded is not in the output. It should be
specified in the executable command line invocation
and also, the symbol must be global as local symbols
are anyways not printed.

Differential revision: https://reviews.llvm.org/D45159

llvm-svn: 329559

lld/test/ELF/cref.s

@@ -6,8 +6,8 @@
 // RUN: rm -f %t.a
 // RUN: llvm-ar rcs %t.a %ta.o
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t3.o
-// RUN: ld.lld -shared -o %t1.so %t1.o -gc-sections
-// RUN: ld.lld -o /dev/null %t1.so %t2.o %t3.o %t.a -cref | FileCheck -strict-whitespace %s
+// RUN: ld.lld -shared -o %t1.so %t1.o
+// RUN: ld.lld -o /dev/null %t1.so %t2.o %t3.o %t.a -gc-sections -cref | FileCheck -strict-whitespace %s
 
 //      CHECK: Symbol                                            File
 // CHECK-NEXT: bar                                               {{.*}}2.o
@@ -19,8 +19,9 @@
 // CHECK-NEXT: baz                                               {{.*}}3.o
 // CHECK-NEXT: zed                                               {{.*}}.a({{.*}}a.o)
 // CHECK-NEXT:                                                   {{.*}}3.o
+// CHECK-NOT:  discarded
 
-.global _start, foo, bar, baz
+.global _start, foo, bar, baz, discarded
 _start:
   call foo
   call bar