[ELF] - Change way how we handle --noinhibit-exec

Previously we handled this option implicitly, only
for infering unresolved symbols handling policy.

ld man says: "--noinhibit-exec Retain the executable
output file whenever it is still usable",
and we may want to handle other cases too.

Differential revision: https://reviews.llvm.org/D35793

llvm-svn: 309091

lld/ELF/Config.h

@@ -44,7 +44,7 @@ enum class DiscardPolicy { Default, All, Locals, None };
 enum class StripPolicy { None, All, Debug };
 
 // For --unresolved-symbols.
-enum class UnresolvedPolicy { ReportError, Warn, WarnAll, Ignore, IgnoreAll };
+enum class UnresolvedPolicy { ReportError, Warn, Ignore, IgnoreAll };
 
 // For --sort-section and linkerscript sorting rules.
 enum class SortSectionPolicy { Default, None, Alignment, Name, Priority };
@@ -128,6 +128,7 @@ struct Configuration {
   bool ICF;
   bool MipsN32Abi = false;
   bool NoGnuUnique;
+  bool NoinhibitExec;
   bool NoUndefinedVersion;
   bool Nostdlib;
   bool OFormatBinary;

lld/ELF/Driver.cpp

@@ -418,9 +418,6 @@ static std::string getRpath(opt::InputArgList &Args) {
 // Determines what we should do if there are remaining unresolved
 // symbols after the name resolution.
 static UnresolvedPolicy getUnresolvedSymbolPolicy(opt::InputArgList &Args) {
-  // -noinhibit-exec or -r imply some default values.
-  if (Args.hasArg(OPT_noinhibit_exec))
-    return UnresolvedPolicy::WarnAll;
   if (Args.hasArg(OPT_relocatable))
     return UnresolvedPolicy::IgnoreAll;
 
@@ -648,6 +645,7 @@ void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   Config->MapFile = Args.getLastArgValue(OPT_Map);
   Config->NoGnuUnique = Args.hasArg(OPT_no_gnu_unique);
   Config->NoUndefinedVersion = Args.hasArg(OPT_no_undefined_version);
+  Config->NoinhibitExec = Args.hasArg(OPT_noinhibit_exec);
   Config->Nostdlib = Args.hasArg(OPT_nostdlib);
   Config->OFormatBinary = isOutputFormatBinary(Args);
   Config->Omagic = Args.hasArg(OPT_omagic);

lld/ELF/Relocations.cpp

@@ -535,6 +535,13 @@ template <class ELFT> static void addCopyRelSymbol(SharedSymbol *SS) {
   In<ELFT>::RelaDyn->addReloc({Target->CopyRel, Sec, Off, false, SS, 0});
 }
 
+static void errorOrWarn(const Twine &Msg) {
+  if (!Config->NoinhibitExec)
+    error(Msg);
+  else
+    warn(Msg);
+}
+
 template <class ELFT>
 static RelExpr adjustExpr(SymbolBody &Body, RelExpr Expr, uint32_t Type,
                           const uint8_t *Data, InputSectionBase &S,
@@ -609,8 +616,8 @@ static RelExpr adjustExpr(SymbolBody &Body, RelExpr Expr, uint32_t Type,
     return toPlt(Expr);
   }
 
-  error("symbol '" + toString(Body) + "' defined in " + toString(Body.File) +
+  errorOrWarn("symbol '" + toString(Body) + "' defined in " +
-        " has no type");
+              toString(Body.File) + " has no type");
   return Expr;
 }
 
@@ -691,12 +698,10 @@ static void reportUndefined(SymbolBody &Sym, InputSectionBase &S,
     Msg += Src + "\n>>>               ";
   Msg += S.getObjMsg<ELFT>(Offset);
 
-  if (Config->UnresolvedSymbols == UnresolvedPolicy::WarnAll ||
+  if (Config->UnresolvedSymbols == UnresolvedPolicy::Warn && CanBeExternal)
-      (Config->UnresolvedSymbols == UnresolvedPolicy::Warn && CanBeExternal)) {
     warn(Msg);
-  } else {
+  else
-    error(Msg);
+    errorOrWarn(Msg);
-  }
 }
 
 template <class RelTy>
@@ -905,9 +910,10 @@ static void scanRelocs(InputSectionBase &Sec, ArrayRef<RelTy> Rels) {
       // We don't know anything about the finaly symbol. Just ask the dynamic
       // linker to handle the relocation for us.
       if (!Target->isPicRel(Type))
-        error("relocation " + toString(Type) +
+        errorOrWarn(
-              " cannot be used against shared object; recompile with -fPIC" +
+            "relocation " + toString(Type) +
-              getLocation<ELFT>(Sec, Body, Offset));
+            " cannot be used against shared object; recompile with -fPIC" +
+            getLocation<ELFT>(Sec, Body, Offset));
 
       In<ELFT>::RelaDyn->addReloc(
           {Target->getDynRel(Type), &Sec, Offset, false, &Body, Addend});

lld/test/ELF/copy-errors.s

@@ -9,6 +9,9 @@
 // CHECK: >>> referenced by {{.*}}.o:(.text+0x1)
 // CHECK: symbol 'zed' defined in {{.*}}.so has no type
 
+// RUN: not ld.lld --noinhibit-exec %t.o %t2.so -o %t 2>&1 | FileCheck %s --check-prefix=NOINHIBIT
+// NOINHIBIT: warning: symbol 'zed' defined in {{.*}}.so has no type
+
 .global _start
 _start:
 call bar

lld/test/ELF/x86-64-dyn-rel-error.s

@@ -10,3 +10,5 @@ _start:
         .long bar
 
 // CHECK: relocation R_X86_64_32 cannot be used against shared object; recompile with -fPIC
+
+// RUN: ld.lld --noinhibit-exec %t.o %t2.so -o %t 2>&1 | FileCheck %s