Fix typo: --nopie -> --no-pie.

[ruiu]

Summary

--nopie was a typo. GNU gold doesn't recognize it. It is also
inconsistent with other options that have --foo and --no-foo.

[brad]

This was NOT a typo.

ELF/Driver.cpp

void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->Nostdlib = Args.hasArg(OPT_nostdlib);
   Config->OFormatBinary = isOutputFormatBinary(Args);
   Config->Omagic = Args.hasFlag(OPT_omagic, OPT_no_omagic, false);
   Config->OptRemarksFilename = Args.getLastArgValue(OPT_opt_remarks_filename);
   Config->OptRemarksWithHotness = Args.hasArg(OPT_opt_remarks_with_hotness);
   Config->Optimize = args::getInteger(Args, OPT_O, 1);
   Config->OrphanHandling = getOrphanHandling(Args);
   Config->OutputFile = Args.getLastArgValue(OPT_o);
-  Config->Pie = Args.hasFlag(OPT_pie, OPT_nopie, false);
+  Config->Pie = Args.hasFlag(OPT_pie, OPT_no_pie, false);
   Config->PrintIcfSections =
       Args.hasFlag(OPT_print_icf_sections, OPT_no_print_icf_sections, false);
   Config->PrintGcSections =
       Args.hasFlag(OPT_print_gc_sections, OPT_no_print_gc_sections, false);
   Config->Rpath = getRpath(Args);
   Config->Relocatable = Args.hasArg(OPT_relocatable);
   Config->SaveTemps = Args.hasArg(OPT_save_temps);
   Config->SearchPaths = args::getStrings(Args, OPT_library_path);

ELF/Options.td

def no_gdb_index: F<"no-gdb-index">,
   HelpText<"Do not generate .gdb_index section">;
 
 def no_gnu_unique: F<"no-gnu-unique">,
   HelpText<"Disable STB_GNU_UNIQUE symbol binding">;
 
 def no_merge_exidx_entries: F<"no-merge-exidx-entries">,
   HelpText<"Disable merging .ARM.exidx entries">;
 
+def no_pie: F<"no-pie">, HelpText<"Do not create a position independent executable">;
+
 def no_threads: F<"no-threads">,
   HelpText<"Do not run the linker multi-threaded">;
 
 def no_whole_archive: F<"no-whole-archive">,
   HelpText<"Restores the default behavior of loading archive members">;
 
 def noinhibit_exec: F<"noinhibit-exec">,
   HelpText<"Retain the executable output file whenever it is still usable">;
 
-def nopie: F<"nopie">, HelpText<"Do not create a position independent executable">;
-
 def no_omagic: Flag<["--"], "no-omagic">, MetaVarName<"<magic>">,
   HelpText<"Do not set the text data sections to be writable">;
 
 def no_print_gc_sections: F<"no-print-gc-sections">,
   HelpText<"Do not list removed unused sections">;
 
 def no_print_icf_sections: F<"no-print-icf-sections">,
   HelpText<"Do not list identical folded sections">;

test/ELF/pie.s

 # CHECK-NEXT:    Type: PT_LOAD
 # CHECK-NEXT:    Offset: 0x0
 # CHECK-NEXT:    VirtualAddress: 0x0
 # CHECK-NEXT:    PhysicalAddress: 0x0
 
 # CHECK:         Type: PT_DYNAMIC
 
 ## Check -nopie
-# RUN: ld.lld -nopie %t1.o -o %t2
+# RUN: ld.lld -no-pie %t1.o -o %t2
 # RUN: llvm-readobj -file-headers -r %t2 | FileCheck %s --check-prefix=NOPIE
 # NOPIE-NOT: Type: SharedObject
 
 .globl _start
 _start: