linux - “__u32 __fswab32(__u32)”不能出现在 netinet/tcp_md5.h 中的常量表达式中

Question

在我的其中一个代码中，我面临以下错误，因为我使用的是 。

========== 错误========

/auto/andpkg/rep_cache//wr-x86-xeon/5.0/sysroot/intel_xeon_32_core-wrs-linux/usr/include/linux/tcp.h:72:17: error: '__u32 __fswab32(__u32)' cannot appear in a constant-expression

==========================

于是我改成netinet/tcp.h，错误就解决了。然而，下一个头文件是 netinet/tcp_md5.h，我发现 netinet/tcp_md5.h 又包含 。所以现在我遇到了相同的编译错误和一些重新声明错误。

========== 重新声明错误==============

在 ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre 包含的文件中-os/netinet/tcp_md5.h:59:0,
从 ../../../../zeromq/conf.x86it/../zeromq-4.0.1/src/options.hpp:38,
从 ../../../../zeromq/conf.x86it/../zeromq-4.0.1/src/ctx.cpp:30: ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:91:0: 错误:“TCP_NODELAY”重新定义 [-Werror] ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing- sw/include/pre-os/netinet/tcp.h:148:0: 注意:这是之前定义的位置../../../../zeromq/conf.x86it/../zeromq -4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:92:0: 错误:“TCP_MAXSEG”重新定义 [-Werror ] ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/netinet/tcp.h:149:0: 注意:这是之前定义的位置../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:94:0: 错误:“TCP_KEEPIDLE”重新定义 [-Werror] ../../。 ./../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/netinet/tcp.h:158: 0:注意:这是之前定义的位置../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:95:0: 错误:“TCP_KEEPINTVL”重新定义 [-Werror] ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/netinet/tcp.h:159:0:注意:这是之前定义的位置../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h :96:0: 错误:“TCP_KEEPCNT”重新定义 [-Werror] ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/netinet/tcp.h:157:0: 注意:这是之前定义的位置

../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:24:8: error: redefinition of 'struct tcphdr' ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/netinet/tcp.h:67:8: error: previous definition of 'struct tcphdr'

========================

========== 常量表达式再次出错==========

../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:72:17: error: '__u32 __fswab32(__u32)' cannot appear in a constant-expression ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:72:17: error: a function call cannot appear in a constant-expression ../../../../zeromq/conf.x86it/../zeromq-4.0.1/../../../../routing-sw/include/pre-os/x86it/os/linux/tcp.h:73:17: error: '__u32 __fswab32(__u32)' cannot appear in a constant-expression

==============

看起来有交叉依赖。有没有人遇到过这个问题？解决此问题的方法是什么？

Answer 1

添加后 -std=c++0x 在 CXXFLAGS ，编译顺利:

CXXFLAGS = -Wall           \
           -pipe            \
           -g                \
           -O2                \
           -fno-crossjumping   \
           -fno-strict-aliasing \
           -march=pentiumpro     \
           --sysroot=/auto/andpkg/rep_cache//wr-x86-xeon/5.0/sysroot/intel_xeon_32_core-wrs-linux \
           -m32                    \
           -Wno-variadic-macros     \
           -std=c++0x