Minimum versions:
g++: 4.8
libboost: 1.54
libssl: 1.0.0
cmake: 3.0

my environment:
Ubuntu 16.04
gcc 5.4.0
GNU Make 4.1

It works.

I see this happening as well on master for Ubuntu. @ichengde is that build from the latest pull of master?

I'm using this build

cmake .. -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF -DBoost_USE_STATIC_LIBS=ON -DBUILD_SAMPLES=OFF -DBUILD_TESTS=OFF -DOPENSSL_ROOT_DIR=/usr/local/ssl

@ichengde note that I'm actually building in a docker environment. The last build I did was maybe 3 months ago. It looks like that compilation flag was added here:

#779

This is the version of g++ I have on my machine

Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 5.4.0-6ubuntu1~16.04.10' --with-bugurl=file:///usr/share/doc/gcc-5/README.Bugs --enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-5 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-5-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-5-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-5-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.10)

However it seems that this is an issue with usage of -Wno-format-truncation and -Wall for gcc versions 5.4.0

http://www.lieberbiber.de/2018/01/14/what-a-gnu-compiler-bug-looks-like/

Interestingly it seems to manifest itself when you can't compile properly. I just made some adjustments so it can build on Ubuntu. Now, that error doesn't happen. It is at the global scope is how it is reported

At global scope:
cc1plus: error: unrecognized command line option ‘-Wno-format-truncation’ [-Werror]
cc1plus: all warnings being treated as errors

Now that it all compiles, no message.

Interestingly it seems to manifest itself when you can't compile properly. I just made some adjustments so it can build on Ubuntu. Now, that error doesn't happen. It is at the global scope is how it is reported

At global scope:
cc1plus: error: unrecognized command line option ‘-Wno-format-truncation’ [-Werror]
cc1plus: all warnings being treated as errors

Now that it all compiles, no message.

I got the same error, which adjustments did you make?

Are you getting any other compilation errors? Mine was related to other compilation errors. Once I remedied them, then the error went away.

I have a PR opened. You can try https://github.com/mobileben/cpprestsdk/tree/issue_887 and see if that helps.

Is that build from the latest pull of master? No, i use 2.10.3 version. Latest commented version, it throws compilation errors.

@ichengde thanks much. If you have the chance, can you try my PR above and see if it remedies the compilation. Just an extra outside source to make sure it builds correctly.

@lookou @ichengde master has been updated. I think (hopefully) you should be able to build from it.

I build it successfully with latest master b211145. Thank you.