attempt to fix protoc build

tools/dockerfile/grpc_artifact_protoc/Dockerfile

@@ -30,24 +30,34 @@ RUN yum install -y git \
                    glibc-devel \
                    glibc-devel.i686
 
-# Install GCC 4.7 to support -static-libstdc++
-RUN wget http://people.centos.org/tru/devtools-1.1/devtools-1.1.repo -P /etc/yum.repos.d
-RUN bash -c 'echo "enabled=1" >> /etc/yum.repos.d/devtools-1.1.repo'
-RUN bash -c "sed -e 's/\$basearch/i386/g' /etc/yum.repos.d/devtools-1.1.repo > /etc/yum.repos.d/devtools-i386-1.1.repo"
-RUN sed -e 's/testing-/testing-i386-/g' -i /etc/yum.repos.d/devtools-i386-1.1.repo
+# Install GCC 4.8
+RUN wget http://people.centos.org/tru/devtools-2/devtools-2.repo -P /etc/yum.repos.d
+RUN bash -c 'echo "enabled=1" >> /etc/yum.repos.d/devtools-2.repo'
+RUN bash -c "sed -e 's/\$basearch/i386/g' /etc/yum.repos.d/devtools-2.repo > /etc/yum.repos.d/devtools-i386-2.repo"
+RUN sed -e 's/testing-/testing-i386-/g' -i /etc/yum.repos.d/devtools-i386-2.repo
 
 # We'll get and "Rpmdb checksum is invalid: dCDPT(pkg checksums)" error caused by
 # docker issue when using overlay storage driver, but all the stuff we need
 # will be installed, so for now we just ignore the error.
 # https://github.com/docker/docker/issues/10180
-RUN yum install -y devtoolset-1.1 \
-                   devtoolset-1.1-libstdc++-devel \
-                   devtoolset-1.1-libstdc++-devel.i686 || true
+RUN yum install -y devtoolset-2-build \
+                   devtoolset-2-toolchain \
+                   devtoolset-2-binutils \
+                   devtoolset-2-gcc \
+                   devtoolset-2-gcc-c++ \
+                   devtoolset-2-libstdc++-devel \
+                   devtoolset-2-libstdc++-devel.i686 || true
+
+# Again, ignore the "Rpmdb checksum is invalid: dCDPT(pkg checksums)" error.
+RUN yum install -y ca-certificates || true  # renew certs to prevent download error for ius-release.rpm
+
+# TODO(jtattermusch): gRPC makefile uses "which" to detect the availability of gcc
+RUN yum install -y which || true
 
 # Update Git to version >1.7 to allow cloning submodules with --reference arg.
 RUN yum remove -y git && yum clean all
 RUN yum install -y https://centos6.iuscommunity.org/ius-release.rpm && yum clean all
 RUN yum install -y git2u && yum clean all
 
-# Start in devtoolset environment that uses GCC 4.7
-CMD ["scl", "enable", "devtoolset-1.1", "bash"]
+# Start in devtoolset environment that uses GCC 4.8
+CMD ["scl", "enable", "devtoolset-2", "bash"]

tools/run_tests/artifacts/build_artifact_protoc.sh

@@ -13,8 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# Use devtoolset environment that has GCC 4.7 before set -ex
-source scl_source enable devtoolset-1.1
+# Use devtoolset environment that has GCC 4.8 before set -ex
+source scl_source enable devtoolset-2
 
 set -ex