Hi Dimitry,
Thank you so much for the reduced testcase! It is able to reproduce
after compiled with clang-8 optimized for X86:
$ clang++ -O3 -S -c JDK-8205969.cpp -o JDK-8205969-opt-8.0.s
$ clang++ -O3 -c JDK-8205969.cpp -o JDK-8205969-opt-8.0.o
$ clang++ -o JDK-8205969-opt-8.0.out JDK-8205969-opt-8.0.o
$ ./JDK-8205969-opt-8.0.out
Segmentation fault
$ cat JDK-8205969-opt-8.0.s
.text
.file "JDK-8205969.cpp"
.globl main # -- Begin function main
.p2align 4, 0x90
.type main,@function
main: # @main
.cfi_startproc
# %bb.0:
xorps %xmm0, %xmm0
movups %xmm0, _ZN15NativeCallStack11EMPTY_STACKE+16(%rip)
movups %xmm0, _ZN15NativeCallStack11EMPTY_STACKE(%rip)
xorl %eax, %eax
retq
.Lfunc_end0:
.size main, .Lfunc_end0-main
.cfi_endproc
# -- End function
.type _ZN15NativeCallStack11EMPTY_STACKE,@object #
@_ZN15NativeCallStack11EMPTY_STACKE
.section .rodata,"a",@progbits
^--- READ-ONLY segment
.globl _ZN15NativeCallStack11EMPTY_STACKE
.p2align 3
_ZN15NativeCallStack11EMPTY_STACKE:
.zero 32
.size _ZN15NativeCallStack11EMPTY_STACKE, 32
.ident "LLVM China clang version 8.0.0
(g...@github.com:llvm-mirror/clang.git
81ef98628ebf5186d746c0986dcbf5073e842043)
(g...@github.com:llvm-mirror/llvm.git
e1aac9723d55497e74d83d216329f08d9842e494) (based on LLVM 8.0.0svn)"
.section ".note.GNU-stack","",@progbits
.addrsig
But it is *not* able to reproduce with clang-8 not optimized for X86:
$ clang++ -O0 -S -c JDK-8205969.cpp -o JDK-8205969-unopt-8.0.s
$ clang++ -O0 -c JDK-8205969.cpp -o JDK-8205969-unopt-8.0.o
$ clang++ -o JDK-8205969-unopt-8.0.out JDK-8205969-unopt-8.0.o
$ ./JDK-8205969-unopt-8.0.out
No segfault
$ cat JDK-8205969-unopt-8.0.s
.text
.file "JDK-8205969.cpp"
.section .text.startup,"ax",@progbits
.p2align 4, 0x90 # -- Begin function
__cxx_global_var_init
.type __cxx_global_var_init,@function
__cxx_global_var_init: # @__cxx_global_var_init
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
movabsq $_ZN15NativeCallStack11EMPTY_STACKE, %rdi
callq _ZN15NativeCallStackC2Ev
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Lfunc_end0:
.size __cxx_global_var_init, .Lfunc_end0-__cxx_global_var_init
.cfi_endproc
# -- End function
.section
.text._ZN15NativeCallStackC2Ev,"axG",@progbits,_ZN15NativeCallStackC2Ev,comdat
.weak _ZN15NativeCallStackC2Ev # -- Begin function
_ZN15NativeCallStackC2Ev
.p2align 4, 0x90
.type _ZN15NativeCallStackC2Ev,@function
_ZN15NativeCallStackC2Ev: # @_ZN15NativeCallStackC2Ev
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
movq %rdi, -8(%rbp)
movq -8(%rbp), %rdi
movl $0, -12(%rbp)
movq %rdi, -24(%rbp) # 8-byte Spill
.LBB1_1: # =>This Inner Loop Header: Depth=1
cmpl $4, -12(%rbp)
jge .LBB1_4
# %bb.2: # in Loop: Header=BB1_1 Depth=1
movslq -12(%rbp), %rax
movq -24(%rbp), %rcx # 8-byte Reload
movq $0, (%rcx,%rax,8)
# %bb.3: # in Loop: Header=BB1_1 Depth=1
movl -12(%rbp), %eax
addl $1, %eax
movl %eax, -12(%rbp)
jmp .LBB1_1
.LBB1_4:
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Lfunc_end1:
.size _ZN15NativeCallStackC2Ev,
.Lfunc_end1-_ZN15NativeCallStackC2Ev
.cfi_endproc
# -- End function
.text
.globl main # -- Begin function main
.p2align 4, 0x90
.type main,@function
main: # @main
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
subq $16, %rsp
movl $0, -4(%rbp)
movabsq $_ZN15NativeCallStack11EMPTY_STACKE, %rdi
callq _ZN15NativeCallStackC2Ev
xorl %eax, %eax
addq $16, %rsp
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Lfunc_end2:
.size main, .Lfunc_end2-main
.cfi_endproc
# -- End function
.section .text.startup,"ax",@progbits
.p2align 4, 0x90 # -- Begin function
_GLOBAL__sub_I_JDK_8205969.cpp
.type _GLOBAL__sub_I_JDK_8205969.cpp,@function
_GLOBAL__sub_I_JDK_8205969.cpp: # @_GLOBAL__sub_I_JDK_8205969.cpp
.cfi_startproc
# %bb.0:
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
callq __cxx_global_var_init
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Lfunc_end3:
.size _GLOBAL__sub_I_JDK_8205969.cpp,
.Lfunc_end3-_GLOBAL__sub_I_JDK_8205969.cpp
.cfi_endproc
# -- End function
.type _ZN15NativeCallStack11EMPTY_STACKE,@object #
@_ZN15NativeCallStack11EMPTY_STACKE
.bss
^--- R/W segment
.globl _ZN15NativeCallStack11EMPTY_STACKE
.p2align 3
_ZN15NativeCallStack11EMPTY_STACKE:
.zero 32
.size _ZN15NativeCallStack11EMPTY_STACKE, 32
.section .init_array,"aw",@init_array
.p2align 3
.quad _GLOBAL__sub_I_JDK_8205969.cpp
.ident "LLVM China clang version 8.0.0
(g...@github.com:llvm-mirror/clang.git
81ef98628ebf5186d746c0986dcbf5073e842043)
(g...@github.com:llvm-mirror/llvm.git
e1aac9723d55497e74d83d216329f08d9842e494) (based on LLVM 8.0.0svn)"
.section ".note.GNU-stack","",@progbits
.addrsig
.addrsig_sym __cxx_global_var_init
.addrsig_sym _GLOBAL__sub_I_JDK_8205969.cpp
.addrsig_sym _ZN15NativeCallStack11EMPTY_STACKE
----- 8< -------- 8< -------- 8< -------- 8< -------- 8< -------- 8< ---
Furthermore clang-3.9.1 *optimized* for X86 is *not* able to reproduce
the issue neither. It behaviors like gcc-6.4.1 and gcc-8. But I will
also check out clang-8 -O3/-O0 for mips64el.
And I am building LLVM 5.0.2 for X86, if still *not* able to
reproduce, it might be reduced the issue to [6, +∞) version range. I
will dig deep-into which commit/review bring in the issue.
在 2018年09月11日 16:55, Dimitry Andric 写道:
Hi Leslie,
The problem really lies in the OpenJDK code, as it is attempting to
write to a const object. If this seems to work with certain compiler(s)
and optimization settings, it is just luck. :-)
Here is a reduced example, which shows the issue:
======================================================================
#include <new>
class NativeCallStack {
public:
static const NativeCallStack EMPTY_STACK;
private:
enum { DEPTH = 4 };
void* stack[DEPTH];
public:
NativeCallStack() {
for (int i = 0; i < DEPTH; ++i) {
stack[i] = nullptr;
}
}
};
const NativeCallStack NativeCallStack::EMPTY_STACK;
int main(void)
{
// The following should segfault, if EMPTY_STACK was placed into .rodata.
::new ((void*)&NativeCallStack::EMPTY_STACK) NativeCallStack();
return 0;
}
======================================================================
clang 7.0.0 rc2 produces this assembly:
.globl main # -- Begin function main
.p2align 4, 0x90
.type main,@function
main: # @main
.cfi_startproc
# %bb.0: # %entry
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
xorps %xmm0, %xmm0
movups %xmm0, NativeCallStack::EMPTY_STACK+16(%rip)
movups %xmm0, NativeCallStack::EMPTY_STACK(%rip)
xorl %eax, %eax
popq %rbp
.cfi_def_cfa %rsp, 8
retq
.Lfunc_end0:
.size main, .Lfunc_end0-main
.cfi_endproc
# -- End function
.type NativeCallStack::EMPTY_STACK,@object #
@NativeCallStack::EMPTY_STACK
.section .rodata,"a",@progbits
.globl NativeCallStack::EMPTY_STACK
.p2align 3
NativeCallStack::EMPTY_STACK:
.zero 32
.size NativeCallStack::EMPTY_STACK, 32
The whole constructor has been optimized out, and EMPTY_STACK has been
replaced by .zero 32, placed in the .rodata segment, which is a
perfectly valid transformation.
Then, in main(), an attempt is made to write to that read-only segment,
which will usually segfault, depending on how strictly the underlying
operating system enforces these protections.
In contrast, gcc 8.2.0 produces:
.globl main
.type main, @function
main:
.LFB74:
.cfi_startproc
movq $0, NativeCallStack::EMPTY_STACK(%rip)
xorl %eax, %eax
movq $0, NativeCallStack::EMPTY_STACK+8(%rip)
movq $0, NativeCallStack::EMPTY_STACK+16(%rip)
movq $0, NativeCallStack::EMPTY_STACK+24(%rip)
ret
.cfi_endproc
.LFE74:
.size main, .-main
.p2align 4,,15
.type _GLOBAL__sub_I__ZN15NativeCallStack11EMPTY_STACKE, @function
_GLOBAL__sub_I__ZN15NativeCallStack11EMPTY_STACKE:
.LFB76:
.cfi_startproc
movq $0, NativeCallStack::EMPTY_STACK(%rip)
movq $0, NativeCallStack::EMPTY_STACK+8(%rip)
movq $0, NativeCallStack::EMPTY_STACK+16(%rip)
movq $0, NativeCallStack::EMPTY_STACK+24(%rip)
ret
.cfi_endproc
.LFE76:
.size _GLOBAL__sub_I__ZN15NativeCallStack11EMPTY_STACKE,
.-_GLOBAL__sub_I__ZN15NativeCallStack11EMPTY_STACKE
.section .ctors,"aw",@progbits
.align 8
.quad _GLOBAL__sub_I__ZN15NativeCallStack11EMPTY_STACKE
.globl NativeCallStack::EMPTY_STACK
.bss
.align 32
.type NativeCallStack::EMPTY_STACK, @object
.size NativeCallStack::EMPTY_STACK, 32
NativeCallStack::EMPTY_STACK:
.zero 32
Here you can see that gcc decided to not place EMPTY_STACK in .rodata,
but in .bss, which is read/write. It adds the global constructor to
the .ctors section, so the dynamic linker is made responsible for
calling it.
Note that now the EMPTY_STACK object is unnecessarily initialized twice,
once by the global constructor, and once in main.
-Dimitry
On 11 Sep 2018, at 03:38, Leslie Zhai <zhaixi...@loongson.cn> wrote:
Hi Dimitry,
Thanks for your kind response!
Thanks for the commit message of Jung's patch, I found that the bug had been
fixed in OpenJDK 12 by Zhengyu https://bugs.openjdk.java.net/browse/JDK-8205965
But only backported to 11. So Jung could backport it for OpenJDK 8, thanks a
lot!
But I argue that the root cause might be in the compiler side, why clang-3.9.1,
gcc-6.4.1 couldn't reproduce the bug? And it might be work for clang-4.0
https://bugs.openjdk.java.net/browse/JDK-8208494 I will test LLVM 5 to check
out whether or not reproducible.
在 2018年09月11日 00:59, Dimitry Andric 写道:
Hi Leslie,
This is likely the same problem as was reported in
https://bugs.freebsd.org/225054#c8, and fixed by the following patch:
https://svnweb.freebsd.org/ports/head/java/openjdk8/files/patch-hotspot_src_share_vm_services_memTracker.cpp?view=markup&pathrev=459368
Can you please try that out, and see if it fixes it for you too?
-Dimitry
On 10 Sep 2018, at 18:20, Leslie Zhai via llvm-dev <llvm-...@lists.llvm.org>
wrote:
Hi all,
OpenJDK8 jdk8u-dev[1] is just able to work after compiled with LLVM 3.9.1 for
X86:
$ ./build/linux-x86_64-normal-server-slowdebug/images/j2sdk-image/bin/java
-version
openjdk version "1.8.0-internal-debug"
OpenJDK Runtime Environment (build
1.8.0-internal-debug-xiangzhai_2018_09_09_21_08-b00)
OpenJDK 64-Bit Server VM (build 25.71-b00-debug, mixed mode)
$ strings
./build/linux-x86_64-normal-server-slowdebug/images/j2sdk-image/bin/java | grep
clang
clang version 3.9.1 (tags/RELEASE_391/final)
But it failed to work after compiled with LLVM 8 for X86:
$ ./build/linux-x86_64-normal-server-fastdebug/images/j2sdk-image/bin/java
-version
Segmentation fault
$ gdb --ex run --args
./build/linux-x86_64-normal-server-fastdebug/images/j2sdk-image/bin/java
-version
GNU gdb (GDB) Fedora 7.12.1-48.fc25
...
Starting program:
/home/xiangzhai/project/jdk8u-llvm/build/linux-x86_64-normal-server-fastdebug/images/j2sdk-image/bin/java
-version
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
[ Legend: Modified register | Code | Heap | Stack | String ]
───────────────────────────────────────────────────────────────────────────────────────────────[
registers ]────
$rax : 0x0
$rbx : 0x0
$rcx : 0x7ffff7315eb0 → 0x00007ffff6ae30a0 →
<NativeCallStack::print_on(outputStream*)+0> xor edx, edx
$rdx : 0x0
$rsp : 0x7fffffff9328 → 0x00007ffff6a76822 →
<MemTracker::init_tracking_level()+178> mov edi, ebx
$rbp : 0x7fffffff93c0 → 0x00007fffffff94f0 → 0x00007fffffff9510 →
0x0000000000000002
$rsi : 0x0
$rdi : 0x7ffff7315e70 → 0x00007ffff7315eb0 → 0x00007ffff6ae30a0 →
<NativeCallStack::print_on(outputStream*)+0> xor edx, edx
$rip : 0x7ffff6ae2f5b → <NativeCallStack::NativeCallStack(int,+0> mov
QWORD PTR [rdi], rcx
$r8 : 0x1
$r9 : 0xf
$r10 : 0x64
$r11 : 0x0
$r12 : 0x7fffffffdc88 → 0x00007fffffffe04c →
"/home/xiangzhai/project/jdk8u-llvm/build/linux-x86[...]"
$r13 : 0x7fffffffdca0 → 0x00007fffffffe0bf → "XDG_VTNR=1"
$r14 : 0x7fffffff9330 → "NMT_LEVEL_10535"
$r15 : 0x6
$eflags: [carry parity adjust zero sign trap INTERRUPT direction overflow
RESUME virtualx86 identification]
$ss: 0x002b $ds: 0x0000 $cs: 0x0033 $es: 0x0000 $gs: 0x0000 $fs: 0x0000
───────────────────────────────────────────────────────────────────────────────────────────────────[
stack ]────
0x00007fffffff9328│+0x00: 0x00007ffff6a76822 →
<MemTracker::init_tracking_level()+178> mov edi, ebx ← $rsp
0x00007fffffff9330│+0x08: "NMT_LEVEL_10535" ← $r14
0x00007fffffff9338│+0x10: 0x0035333530315f4c ("L_10535"?)
0x00007fffffff9340│+0x18: 0x0000000000000001
0x00007fffffff9348│+0x20: 0x0000000000602190 → 0x00007ffff5eb7000 →
0x00010102464c457f
0x00007fffffff9350│+0x28: 0x0000000000000004
0x00007fffffff9358│+0x30: 0x000000066474e551
0x00007fffffff9360│+0x38: 0x0000000000000000
────────────────────────────────────────────────────────────────────────────────────────[
code:i386:x86-64 ]────
0x7ffff6ae2f4b <print_owned_locks_on_error(outputStream*)+187> add eax,
0x1f0f00
0x7ffff6ae2f50 <NativeCallStack::NativeCallStack(int,+0> mov rcx, QWORD
PTR [rip+0x842781] # 0x7ffff73256d8
0x7ffff6ae2f57 <NativeCallStack::NativeCallStack(int,+0> add rcx, 0x10
→ 0x7ffff6ae2f5b <NativeCallStack::NativeCallStack(int,+0> mov QWORD PTR
[rdi], rcx
0x7ffff6ae2f5e <NativeCallStack::NativeCallStack(int,+0> mov DWORD PTR
[rdi+0x28], 0x0
0x7ffff6ae2f65 <NativeCallStack::NativeCallStack(int,+0> add rdi, 0x8
0x7ffff6ae2f69 <NativeCallStack::NativeCallStack(int,+0> test edx, edx
0x7ffff6ae2f6b <NativeCallStack::NativeCallStack(int,+0> je 0x7ffff6ae2f7b
<NativeCallStack::NativeCallStack(int, bool)+43>
0x7ffff6ae2f6d <NativeCallStack::NativeCallStack(int,+0> mov eax, esi
─────────[
source:/home/xiangzhai/project/jdk8u-llvm/hotspot/src/share/vm/utilities/nativeCallStack.cpp+33
]────
28 #include "utilities/nativeCallStack.hpp"
29
30 const NativeCallStack NativeCallStack::EMPTY_STACK(0, false);
31
32 NativeCallStack::NativeCallStack(int toSkip, bool fillStack) :
→ 33 _hash_value(0) {
34
35 #if !PLATFORM_NATIVE_STACK_WALKING_SUPPORTED
36 fillStack = false;
37 #endif
38
─────────────────────────────────────────────────────────────────────────────────────────────────[
threads ]────
[#0] Id 1, Name: "java", stopped, reason: SIGSEGV
───────────────────────────────────────────────────────────────────────────────────────────────────[
trace ]────
[#0] 0x7ffff6ae2f5b → Name: NativeCallStack::NativeCallStack(this=0x7ffff7315e70
<NativeCallStack::EMPTY_STACK>, toSkip=0x0, fillStack=0x0)
[#1] 0x7ffff6a76822 → Name: MemTracker::init_tracking_level()
[#2] 0x7ffff62eff49 → Name: MemTracker::tracking_level()
[#3] 0x7ffff62eff49 → Name: ResourceObj::operator new(size=0x20,
type=ResourceObj::STACK_OR_EMBEDDED, flags=<optimized out>)
[#4] 0x7ffff61369ec → Name: _GLOBAL__sub_I_c1_Greedy.cpp()
[#5] 0x7ffff7de7d9a → Name: call_init(l=<optimized out>, argc=0x2,
argv=0x7fffffffdc88, env=0x7fffffffdca0)
[#6] 0x7ffff7de7eab → Name: call_init(env=0x7fffffffdca0, argv=0x7fffffffdc88,
argc=0x2, l=<optimized out>)
[#7] 0x7ffff7de7eab → Name: _dl_init(main_map=0x602190, argc=0x2,
argv=0x7fffffffdc88, env=0x7fffffffdca0)
[#8] 0x7ffff7dece46 → Name: dl_open_worker(a=0x7fffffff97e0)
[#9] 0x7ffff7de7c44 → Name: _dl_catch_error(objname=0x7fffffff97d0,
errstring=0x7fffffff97d8, mallocedp=0x7fffffff97cf, operate=0x7ffff7decae0
<dl_open_worker>, args=0x7fffffff97e0)
────────────────────────────────────────────────────────────────────────────────────────────────────────────────
0x00007ffff6ae2f5b in NativeCallStack::NativeCallStack (this=0x7ffff7315e70
<NativeCallStack::EMPTY_STACK>, toSkip=0x0, fillStack=0x0) at
/home/xiangzhai/project/jdk8u-llvm/hotspot/src/share/vm/utilities/nativeCallStack.cpp:33
33 _hash_value(0) {
gef➤ c
Continuing.
Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
gef➤
----- 8< -------- 8< -------- 8< -------- 8< -------- 8< -------- 8< ---
I started to use and contribute clang static analyzer[2] just for finding the
bugs for open source software from LLVM 3.x, perhaps it is a bug of LLVM 8,
because jdk8u is just able to print out '-version' after compiled with
llvm-3.9.1, I will rebuild the LLVM 8 again, then rebuild jdk8u for triple
check.
1. Workaround-compile-with-llvm.patch
https://raw.githubusercontent.com/xiangzhai/jdk8u-dev/master/Workaround-compile-with-llvm.patch
2.
https://github.com/llvm-mirror/clang/commit/a530e823ed2793ac149de7a984014e242a787682#diff-ff9160d4628cb9b6186559837c2c8668
3. The build option of LLVM 8 (bootstrap with LLVM 3.9.1):
cmake .. -DCMAKE_BUILD_TYPE=Release \
-DCMAKE_C_COMPILER=clang \
-DCMAKE_CXX_COMPILER=clang++ \
-DCMAKE_C_FLAGS="-fPIC" \
-DCMAKE_CXX_FLAGS="-std=c++11 -fPIC" \
-DLLVM_BUILD_LLVM_DYLIB=ON \
-DLLVM_LINK_LLVM_DYLIB=ON \
-DLLVM_INSTALL_UTILS=ON \
-DLLVM_ENABLE_RTTI=ON \
-DLLVM_ENABLE_FFI=ON \
-DLLVM_ENABLE_EH=ON \
-DLLVM_BUILD_TESTS=ON \
-DLLVM_BUILD_DOCS=OFF \
-DLLVM_ENABLE_SPHINX=OFF \
-DLLVM_ENABLE_DOXYGEN=OFF \
-DLLDB_DISABLE_LIBEDIT=1 \
-DSPHINX_WARNINGS_AS_ERRORS=OFF \
-DFFI_INCLUDE_DIR=$(pkg-config --variable=includedir libffi) \
-DFFI_LIBRARY_DIR:PATH="$(pkg-config --variable=libdir libffi)" \
-DLLVM_BINUTILS_INCDIR=/usr/include \
-DLLVM_LIBDIR_SUFFIX=64 \
-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=ON \
-DLIBUNWIND_ENABLE_SHARED=ON \
-DLIBCXXABI_USE_LLVM_UNWINDER=ON \
-DLLDB_TEST_C_COMPILER=clang \
-DLLDB_TEST_CXX_COMPILER=clang++ \
-DLLVM_DEFAULT_TARGET_TRIPLE="x86_64-redhat-linux" \
-DCLANG_VENDOR="LLVM China"
4. $ clang -v
LLVM China clang version 8.0.0 (g...@github.com:llvm-mirror/clang.git
81ef98628ebf5186d746c0986dcbf5073e842043) (g...@github.com:llvm-mirror/llvm.git
e1aac9723d55497e74d83d216329f08d9842e494) (based on LLVM 8.0.0svn)
Target: x86_64-redhat-linux
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/i686-redhat-linux/6.4.1
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-redhat-linux/6.4.1
Found candidate GCC installation: /usr/lib/gcc/i686-redhat-linux/6.4.1
Found candidate GCC installation: /usr/lib/gcc/x86_64-redhat-linux/6.4.1
Selected GCC installation: /usr/bin/../lib/gcc/x86_64-redhat-linux/6.4.1
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Selected multilib: .;@m64
--
Regards,
Leslie Zhai
_______________________________________________
LLVM Developers mailing list
llvm-...@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
--
Regards,
Leslie Zhai
--
Regards,
Leslie Zhai
