Bug 800478

Created attachment 567970 [details]
Preprocessed source

Description of problem:
When trying to rebuild some Fedora packages using LLVM/clang instead of GCC, clang segfaults. With LLVM 2.9 several packages could be rebuilt, now I did not find a single one that would pass.

Version-Release number of selected component (if applicable):
llvm-3.0-8.fc18

How reproducible:
Always

Steps to Reproduce:
1. Download the preprocessed source from attachment
2. run "/usr/bin/clang -cc1 -triple x86_64-redhat-linux-gnu -emit-llvm-bc -disable-free -disable-llvm-verifier -main-file-name printf-args.c -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-linker-version 2.22.52.0.1 -momit-leaf-frame-pointer -v -g -coverage-file printf-args.o -resource-dir /usr/bin/../lib/clang/3.0 -D HAVE_CONFIG_H -D HAVE_LSTAT -I . -fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib/clang/3.0/include -internal-externc-isystem /usr/include -O0 -Wall -ferror-limit 19 -fmessage-length 0 -fgnu-runtime -fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fexceptions -fdiagnostics-show-option -o printf-args.o -x c printf-args.pp.c"
  
Actual results:
clang -cc1 version 3.0 based upon llvm 3.0 hosted on x86_64-redhat-linux-gnu
#include "..." search starts here:
#include <...> search starts here:
 .
 /usr/local/include
 /usr/bin/../lib/clang/3.0/include
 /usr/include
End of search list.
0  libLLVM-3.0.so  0x00007f1f25e1a0bf
1  libLLVM-3.0.so  0x00007f1f25e1a529
2  libpthread.so.0 0x00007f1f2565efb0
3  clang           0x0000000000c5db02
4  clang           0x0000000000c5e4f2
5  clang           0x0000000000c5ecf7
6  clang           0x0000000000c6037d clang::runUninitializedVariablesAnalysis(clang::DeclContext const&, clang::CFG const&, clang::AnalysisContext&, clang::UninitVariablesHandler&, clang::UninitVariablesAnalysisStats&) + 1597
7  clang           0x0000000000af075a clang::sema::AnalysisBasedWarnings::IssueWarnings(clang::sema::AnalysisBasedWarnings::Policy, clang::sema::FunctionScopeInfo*, clang::Decl const*, clang::BlockExpr const*) + 970
8  clang           0x00000000008a338c clang::Sema::PopFunctionOrBlockScope(clang::sema::AnalysisBasedWarnings::Policy const*, clang::Decl const*, clang::BlockExpr const*) + 172
9  clang           0x00000000009209ee clang::Sema::ActOnFinishFunctionBody(clang::Decl*, clang::Stmt*, bool) + 334
10 clang           0x00000000008481e0 clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) + 192
11 clang           0x0000000000859564 clang::Parser::ParseFunctionDefinition(clang::Parser::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&) + 964
12 clang           0x000000000086e7d7 clang::Parser::ParseDeclGroup(clang::Parser::ParsingDeclSpec&, unsigned int, bool, clang::SourceLocation*, clang::Parser::ForRangeInit*) + 807
13 clang           0x00000000008532e5 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsingDeclSpec&, clang::AccessSpecifier) + 149
14 clang           0x0000000000853765 clang::Parser::ParseDeclarationOrFunctionDefinition(clang::ParsedAttributes&, clang::AccessSpecifier) + 565
15 clang           0x000000000085718d clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::Parser::ParsingDeclSpec*) + 2157
16 clang           0x00000000008574c0 clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&) + 144
17 clang           0x0000000000830c0d clang::ParseAST(clang::Sema&, bool) + 269
18 clang           0x00000000007196f3 clang::CodeGenAction::ExecuteAction() + 51
19 clang           0x000000000060f5b3 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) + 307
20 clang           0x00000000005f9524 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) + 980
21 clang           0x00000000005f1204 cc1_main(char const**, char const**, char const*, void*) + 740
22 clang           0x00000000005f00b8 main + 7096
23 libc.so.6       0x00007f1f24689735 __libc_start_main + 245
24 clang           0x00000000005f0d61
Stack dump:
0.	Program arguments: /usr/bin/clang -cc1 -triple x86_64-redhat-linux-gnu -emit-llvm-bc -disable-free -disable-llvm-verifier -main-file-name printf-args.c -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-linker-version 2.22.52.0.1 -momit-leaf-frame-pointer -v -g -coverage-file printf-args.o -resource-dir /usr/bin/../lib/clang/3.0 -D HAVE_CONFIG_H -D HAVE_LSTAT -I . -fmodule-cache-path /var/tmp/clang-module-cache -internal-isystem /usr/local/include -internal-isystem /usr/bin/../lib/clang/3.0/include -internal-externc-isystem /usr/include -O0 -Wall -ferror-limit 19 -fmessage-length 0 -fgnu-runtime -fobjc-runtime-has-arc -fobjc-runtime-has-weak -fobjc-fragile-abi -fexceptions -fdiagnostics-show-option -o printf-args.o -x c printf-args.pp.c 
1.	<eof> parser at end of file
2.	printf-args.c:40:1: parsing function body 'printf_fetchargs'
Segmentation fault

Expected results:
The source compiles with no error.

Additional info:
Source comes from gzip-1.4-6.fc17. The error originates in running from rpmbuild (which appends the flags). A simple LLVM/clang build simulation can be done:
1) download the SRPM (http://kojipkgs.fedoraproject.org/packages/gzip/1.4/6.fc17/src/gzip-1.4-6.fc17.src.rpm)
2) rpm -ivh gzip-1.4-6.fc17.src.rpm
3) add the
"export CC=clang" and
LDFLAGS="-Wl,--plugin,/usr/lib64/llvm/LLVMgold.so -Wl,--plugin-opt,also-emit-llvm"
lines to the beginning of %build section of the specfile
4) switch the linker to ld.gold
5) rpmbuild -bb ~/rpmbuild/SPECS/gzip.spec

Same trick works and produces the error on different simple packages (eg. ncurses, libselinux, btparser), you just eventually need to add "export CXX=clang".