http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54328
Bug #: 54328
Summary: capture pointer by value is not correct
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: yaoyuan1...@gmail.com
int a[1];
a[0] = 1;
auto fun = [a]{cout<<a[0]<<endl;};
fun();
a[0] = 2;
fun();
This will produce:
1
1
I think it shoud be:
1
2
g++ -std=c++0x -v -save-temps -Wall t.cpp outputs:
使用内建 specs。
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/lto-wrapper
目标：x86_64-unknown-linux-gnu
配置为：../gcc-trunk/configure --disable-multilib --enable-checking=release
--enable-languages=c,c++ --enable-threads=posix --prefix=/home/mww/.gcc
线程模型：posix
gcc 版本 4.8.0 20120816 (experimental) (GCC)
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-save-temps' '-Wall' '-shared-libgcc'
'-mtune=generic' '-march=x86-64'
/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/cc1plus -E -quiet -v
-D_GNU_SOURCE t.cpp -mtune=generic -march=x86-64 -std=c++11 -Wall
-fpch-preprocess -o t.ii
忽略不存在的目录“/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../x86_64-unknown-linux-gnu/include”
#include "..." 搜索从这里开始：
#include <...> 搜索从这里开始：
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../include/c++/4.8.0
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../include/c++/4.8.0/x86_64-unknown-linux-gnu
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../include/c++/4.8.0/backward
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/include
/usr/local/include
/home/mww/.gcc/include
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/include-fixed
/usr/include
搜索列表结束。
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-save-temps' '-Wall' '-shared-libgcc'
'-mtune=generic' '-march=x86-64'
/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/cc1plus
-fpreprocessed t.ii -quiet -dumpbase t.cpp -mtune=generic -march=x86-64
-auxbase t -Wall -std=c++11 -version -o t.s
GNU C++ (GCC) 版本 4.8.0 20120816 (experimental) (x86_64-unknown-linux-gnu)
由 GNU C 版本 4.8.0 20120816 (experimental) 编译， GMP version 5.0.5, MPFR
version 3.1.1, MPC version 0.9
GGC 准则：--param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU C++ (GCC) 版本 4.8.0 20120816 (experimental) (x86_64-unknown-linux-gnu)
由 GNU C 版本 4.8.0 20120816 (experimental) 编译， GMP version 5.0.5, MPFR
version 3.1.1, MPC version 0.9
GGC 准则：--param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 68a842c32ece7e9b3774793c3488162d
t.cpp: 在函数‘int main(int, const char**)’中:
t.cpp:7:6: 警告： variable ‘a’ set but not used [-Wunused-but-set-variable]
int a[1];
^
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-save-temps' '-Wall' '-shared-libgcc'
'-mtune=generic' '-march=x86-64'
as -v --64 -o t.o t.s
GNU assembler version 2.20.1 (x86_64-linux-gnu) using BFD version (GNU Binutils
for Ubuntu) 2.20.1-system.20100303
COMPILER_PATH=/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/:/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/:/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/:/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/:/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/
LIBRARY_PATH=/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/:/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../lib64/:/lib/../lib64/:/usr/lib/../lib64/:/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-save-temps' '-Wall' '-shared-libgcc'
'-mtune=generic' '-march=x86-64'
/home/mww/.gcc/libexec/gcc/x86_64-unknown-linux-gnu/4.8.0/collect2
--eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2
/usr/lib/../lib64/crt1.o /usr/lib/../lib64/crti.o
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/crtbegin.o
-L/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0
-L/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../../../lib64
-L/lib/../lib64 -L/usr/lib/../lib64
-L/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/../../.. t.o -lstdc++
-lm -lgcc_s -lgcc -lc -lgcc_s -lgcc
/home/mww/.gcc/lib/gcc/x86_64-unknown-linux-gnu/4.8.0/crtend.o
/usr/lib/../lib64/crtn.o
