trunk llvm (r140196) fails to build for linux/ppc

[jeremyhu]

Bugzilla Link	10969
Version	trunk
OS	Linux
Attachments	PPCAsmPrinter.pp.c.bz2
CC	@efriedma-quic

Extended Description

if g++ -I/home/jeremy/src/llvm/build.ppc/include -I/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC -I/home/jeremy/src/llvm/include -I/home/jeremy/src/llvm/lib/Target/PowerPC -D_DEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -O3 -fomit-frame-pointer -g -fno-exceptions -fno-rtti -fPIC -Woverloaded-virtual -Wcast-qual -pedantic -Wno-long-long -Wall -W -Wno-unused-parameter -Wwrite-strings -c -MMD -MP -MF "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d.tmp" -MT "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.o" -MT "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d" /home/jeremy/src/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp -o /home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.o ;
then /bin/mv -f "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d.tmp" "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d"; else /bin/rm "/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d.tmp"; exit 1; fi
In file included from /home/jeremy/src/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h:41:0,
from /home/jeremy/src/llvm/lib/Target/PowerPC/MCTargetDesc/PPCBaseInfo.h:20,
from /home/jeremy/src/llvm/lib/Target/PowerPC/PPC.h:18,
from /home/jeremy/src/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp:20:
/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/PPCGenRegisterInfo.inc:17:11: error: expected identifier before numeric constant
/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/PPCGenRegisterInfo.inc:17:11: error: expected unqualified-id before numeric constant
In file included from /usr/include/c++/4.5/new:42:0,
from /usr/include/c++/4.5/ext/new_allocator.h:33,
from /usr/include/c++/4.5/powerpc-linux-gnu/bits/c++allocator.h:34,
from /usr/include/c++/4.5/bits/allocator.h:48,
from /usr/include/c++/4.5/string:43,
from /home/jeremy/src/llvm/include/llvm/ADT/StringRef.h:16,
from /home/jeremy/src/llvm/include/llvm/Support/ErrorHandling.h:19,
from /home/jeremy/src/llvm/lib/Target/PowerPC/MCTargetDesc/PPCBaseInfo.h:21,
from /home/jeremy/src/llvm/lib/Target/PowerPC/PPC.h:18,
from /home/jeremy/src/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp:20:
/usr/include/c++/4.5/exception:37:37: error: expected ‘}’ before end of line
/usr/include/c++/4.5/exception:37:37: error: expected declaration before end of line
/bin/rm: cannot remove `/home/jeremy/src/llvm/build.ppc/lib/Target/PowerPC/Release+Debug+Asserts/PPCAsmPrinter.d.tmp': No such file or directory

preprocessed source attached.

[jeremyhu]

Sorry for compressing the preprocessed source, but bugzilla wouldn't take it otherwise...

[efriedma-quic]

Try putting -UPPC into your CPPFLAGS.

[efriedma-quic]

Err, I mean CXXFLAGS.

[jeremyhu]

I can't speak to the functional effect, but appending -UPPC when compiling that one file causes it to build.

[efriedma-quic]

Okay... then a configure patch or something that does the equivalent automatically would probably be appropriate.

[llvmbot]

Since r135184.

I suggest a patch;

--- a/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h
+++ b/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h
@@ -34,6 +34,10 @@ MCAsmBackend *createPPCAsmBackend(const Target &T, StringRef TT);

} // End llvm namespace

+// Generated files will use "namespace PPC". To avoid symbol clash,
+// undefine PPC here. PPC may be predefined on some hosts.
+#undef PPC
+
// Defines symbolic names for PowerPC registers. This defines a mapping from
// register name to register number.
//

[llvmbot]

Oh no, it was not enough. I should #undef PPC in two place.

lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h
lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h

[llvmbot]

Oh no, it was not enough. I should #undef PPC in two place.

lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h
lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h

hi, i just try to build llvm-3.0 (stable) on linux ppc32 (CRUX PPC 2.7) with gcc-4.5.3, binutils-2.21.1, glibc-2.12.2 .

As the above suggestions i applied a patch like this one:
--- llvm-3.0.src/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h 2011-07-26 01:24:55.000000000 +0200
+++ llvm-3.0.src/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h 2011-12-02 02:04:06.000000000 +0100
@@ -34,6 +34,10 @@

} // End llvm namespace

+// Generated files will use "namespace PPC". To avoid symbol clash,
+// undefine PPC here. PPC may be predefined on some hosts.
+#undef PPC
+
// Defines symbolic names for PowerPC registers. This defines a mapping from
// register name to register number.
//
--- llvm-3.0.src/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h 2011-07-26 02:24:13.000000000 +0200
+++ llvm-3.0.src/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h 2011-12-02 02:05:22.000000000 +0100
@@ -14,6 +14,10 @@
#ifndef LLVM_TARGET_POWERPC_PPCPREDICATES_H
#define LLVM_TARGET_POWERPC_PPCPREDICATES_H

+// Generated files will use "namespace PPC". To avoid symbol clash,
+// undefine PPC here. PPC may be predefined on some hosts.
+#undef PPC
+
namespace llvm {
namespace PPC {
/// Predicate - These are "(BI << 5) | BO" for various predicates.

but i got this further error:

[...]
make[3]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine/JIT' make[3]: Entering directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine/MCJIT'
llvm[3]: Compiling Intercept.cpp for Release build
llvm[3]: Compiling MCJIT.cpp for Release build
llvm[3]: Building Release Archive Library libLLVMMCJIT.a
make[3]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine/MCJIT' make[3]: Entering directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine/RuntimeDyld'
llvm[3]: Compiling RuntimeDyld.cpp for Release build
llvm[3]: Compiling RuntimeDyldMachO.cpp for Release build
llvm[3]: Building Release Archive Library libLLVMRuntimeDyld.a
make[3]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine/RuntimeDyld' make[2]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/ExecutionEngine'
make[2]: Entering directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/Linker' llvm[2]: Compiling LinkArchives.cpp for Release build llvm[2]: Compiling LinkItems.cpp for Release build llvm[2]: Compiling LinkModules.cpp for Release build llvm[2]: Compiling Linker.cpp for Release build llvm[2]: Building Release Archive Library libLLVMLinker.a make[2]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/Linker'
make[2]: Entering directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/MC' llvm[2]: Compiling ELFObjectWriter.cpp for Release build In file included from ELFObjectWriter.cpp:33:0: ../Target/PowerPC/MCTargetDesc/PPCFixupKinds.h:16:11: error: expected identifier before numeric constant ../Target/PowerPC/MCTargetDesc/PPCFixupKinds.h:16:11: error: expected unqualified-id before numeric constant ELFObjectWriter.cpp:1832:1: error: expected '}' at end of input /bin/rm: cannot remove /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/MC/Release/ELFObjectWriter.d.tmp': No such file or directory
make[2]: *** [/mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/MC/Release/ELFObjectWriter.o] Error 1
make[2]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib/MC' make[1]: *** [MC/.makeall] Error 2 make[1]: Leaving directory /mnt/EXT/00/llvm/work/src/llvm-3.0.src/lib'
make: *** [all] Error 1

[llvmbot]

I notice the PPC definition problem is still present in trunk... Any plan to commit one of the "workarounds" ?

On a second thought, it seems to me that it would be better to change the namespace, for example to "PowerPC". Would that be a problem ?

I am basically completely new to llvm (messing around with sparse-llvm and llvmpipe a bit) so I may well be missing something here, but if you think that approach is correct, I can give it a try & submit a patch.

Cheers,
Ben.

[llvmbot]

Hrm, ok so changing the namespace name would be a fairly enormous & invasive patch... maybe not the best approach in the end.

[llvmbot]

you can build it with:

export CXXFLAGS="$CXXFLAGS -UPPC"

anyway it 'll fail the 'make check' stage
http://lists.cs.uiuc.edu/pipermail/llvmdev/2011-December/045836.html

and it's not only a test suite's bug because the fresh built clang is faulty (e.g. it's unable to build itself).

--nico

[llvmbot]

Well, the ppc backend seem to have been rotting for a while now :-)

I want to have a look and see if I can fix some of it, but I know nothing about llvm and very little about compilers, so it will take a bit of time for me to catch up.

In case you're interested to work on these too:

One thing I've identified (I'll open a separate bug when I have a nice repro-case) is that sign extension from i1 to something larger doesn't work properly. In llvm lingua, it's expected to sign extend to -1 and things like llvmpipe generate code that relies on it (generating masks etc...) but the generated code I've seen with 3.0 and later zeems to zero extend instead (ie. treat i1 as unsigned basically). I need to figure out whether that's a generic problem or a specific failing construct, working on it.

I've also had asserts with the latest svn checkouts in the optim pass that tries to scalarize vectors, something deep in a notifier related to an SDValue object ID not being what it's expected ... I need to understand a lot more of llvm before I can fix that.

Anyway, I'll try to produce simple repro cases, open separate bugs for them, and then start learning things see if I can fix them myself in case nobody with more clues steps in.

[pjaaskel]

fixes the compilation issue
The build of the PPC backend on PPC is still broken on Linux (at least on Debian Sid with gcc 4.6).

This patch fixes the build without the need to add -UPPC to the compiler flags (which sounds a bit too intrusive approach to me). It simply #undefs the compiler-defined PPC close to the places where it causes compilation problems.

Please apply both to LLVM 3.2 and trunk.