OSX: 'upc_pgm_info': mach-o section specifier requires a segment and section separated by a comma

[swatanabe]

On Macos/Darwin, the make fails with

fatal error: error in backend: Global variable 'GCCUPCConfig' has an invalid
section specifier 'upc_pgm_info': mach-o section specifier requires a
segment and section separated by a comma.

This GCCUPCConfig variable is generated by this section of code.

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 9a55c08..895d80b 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
[...]
void CodeGenModule::Release() {

• if (getContext().getLangOpts().UPC) {
• llvm::SmallString<64> str;
• str += "$GCCUPCConfig: (";
• str += getModule().getModuleIdentifier();
• str += ") ";
• unsigned Threads = getContext().getLangOpts().UPCThreads;
• if (Threads == 0) {

•  str += "dynamicthreads";
  

• } else {

•  str += "staticthreads=";
  

•  llvm::APInt(32, Threads).toStringUnsigned(str);
  

• }
• str += " process$";
• llvm::GlobalVariable * conf =

•  new llvm::GlobalVariable(getModule(), llvm::ArrayType::get(Int8Ty, str.size
  

•                           true, llvm::GlobalValue::InternalLinkage,
  

•                           llvm::ConstantDataArray::getString(getLLVMContext(
  

•                           "GCCUPCConfig");
  

• conf->setSection("upc_pgm_info");
• AddUsedGlobal(conf);
• }

Note the "setSection" call above.

This small test program indicates the expected section name syntax on a Mach OS based system.

static const char GCCUPCConfig[]

if MACH

attribute ((section("DATA,upc_pgm_info"))) __attribute ((used)) =

else

attribute ((section("upc_pgm_info"))) attribute ((used)) =

endif

"$GCCUPCConfig: (" BASE_FILE ") " "$";

int main(void)
{
return 0;
}

I think that the lack of the ""__DATA,upc_pgm_info" syntax might be the source of the problem, but am unsure how this might be best parametrized within the compiler. Perhaps there is already some mechanism to achieve this OS dependent behavior?

[swatanabe]

I think the right way to solve this is to move this definition back into gcc-upc-lib.h. The only reason for the divergence from gupc is that I didn't completely understand how gupc handles it when I wrote this originally.

[nenadv]

I tried to push the way through this error by adding appropriate sections (__DATA) where needed. Made the following changes:

diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index f7c65dd..ebd7ed7 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -202,7 +202,11 @@ CodeGenFunction::CreateStaticVarDecl(const VarDecl &D,
if (Linkage != llvm::GlobalValue::InternalLinkage)
GV->setVisibility(CurFn->getVisibility());
if(SharedInit)
+#if MACH

• GV->setSection("__DATA,upc_shared");
  +#else
  GV->setSection("upc_shared");
  +#endif
  return GV;
  }

diff --git a/lib/CodeGen/CGStmtUPC.cpp b/lib/CodeGen/CGStmtUPC.cpp
index 707f92b..1186d75 100644
--- a/lib/CodeGen/CGStmtUPC.cpp
+++ b/lib/CodeGen/CGStmtUPC.cpp
@@ -68,7 +68,11 @@ llvm::Constant *CodeGenModule::getUPCFenceVar() {
llvm::GlobalValue::LinkOnceODRLinkage,
llvm::ConstantInt::get(IntTy, 0),
"upc_fence_var");
+#if __MACH

• GV->setSection("DATA,upc_shared");
  +#else
  GV->setSection("upc_shared");
  +#endif
  UPCFenceVar = GV;
  }
  return UPCFenceVar;
  diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
  index 895d80b..8bef985 100644
  --- a/lib/CodeGen/CodeGenModule.cpp
  +++ b/lib/CodeGen/CodeGenModule.cpp
  @@ -168,7 +168,11 @@ void CodeGenModule::Release() {
  true, llvm::GlobalValue::InternalLinkage,
  llvm::ConstantDataArray::getString(getLLVMContext(), str),
  "GCCUPCConfig");
  +#if __MACH
• conf->setSection("__DATA,upc_pgm_info");
  +#else
  conf->setSection("upc_pgm_info");
  +#endif
  AddUsedGlobal(conf);
  }
  EmitDeferred();
  @@ -1655,7 +1659,11 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {

SetCommonAttributes(D, GV);
if(ASTTy.getQualifiers().hasShared())
+#if MACH

• GV->setSection("__DATA,upc_shared");
  +#else
  GV->setSection("upc_shared");
  +#endif

// Emit the initializer function if necessary.
if (NeedsGlobalCtor || NeedsGlobalDtor)
diff --git a/runtime/libupc/CMakeLists.txt b/runtime/libupc/CMakeLists.txt
index fb93628..893d1b9 100644
--- a/runtime/libupc/CMakeLists.txt
+++ b/runtime/libupc/CMakeLists.txt
@@ -447,7 +447,7 @@ macro(add_crt_target name opts)
list(APPEND objects ${obj})
add_custom_target(${name} ALL DEPENDS ${obj})
add_custom_command(OUTPUT ${obj}

• COMMAND ${CMAKE_C_COMPILER} -c -o ${obj} ${PROJECT_SOURCE_DIR}/upc-crtstuff.c -I${PROJECT_SOURCE_DIR}/config/default -I${
• COMMAND ${CMAKE_C_COMPILER} -c -o ${obj} ${PROJECT_SOURCE_DIR}/upc-crtstuff.c -I${PROJECT_SOURCE_DIR}/config/darwin -I${P
  MAIN_DEPENDENCY upc-crtstuff.c
  IMPLICIT_DEPENDENCY upc-crtstuff.c
  VERBATIM)

---

The only change that is problematic is the one in runtime/libupc/CMakeLists.txt. I am not familiar with Cmake and don;t know how to change the include based on the system it is building on.

After this I was able to rebuild everything to the end. And did not run into the perl error. Which is interesting.

[gary-funck]

On 03/04/13 17:26:18, Nenad Vukicevic wrote:

I tried to push the way through this error by adding
appropriate sections (__DATA) where needed. Made the following changes:
[...]
After this I was able to rebuild everything to the end. And
did not run into the perl error. Which is interesting.

If you didn't 'make clean' or start from scratch, the .ld
file might've already been created, and would be empty.

Try it from scratch, with the default -j switch.

[swatanabe]

Preprocessor directives aren't really the right way to handle this, as they break cross-compilation. I don't have a mac to test with, but I'll try to put something together today.

[nenadv]

It looks like we forgot one change that made some tests fail on Mac OS:

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index ca5bf3a..d703484 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -458,7 +458,10 @@ void CodeGenModule::EmitUPCInits(const CtorList &Fns, const char *Globa
                              llvm::GlobalValue::AppendingLinkage,
                              llvm::ConstantArray::get(AT, Ctors),
                              GlobalName);
-    GV->setSection("upc_init_array");
+    if(isTargetDarwin())
+      GV->setSection("__DATA,upc_init_array");
+    else
+      GV->setSection("upc_init_array");
   }
 }

[swatanabe]

This patch looks fine. Please commit it.