diff --git a/src/ci/docker/cross2/Dockerfile b/src/ci/docker/cross2/Dockerfile
index f5fc06767ce..029d2c18d4a 100644
--- a/src/ci/docker/cross2/Dockerfile
+++ b/src/ci/docker/cross2/Dockerfile
@@ -36,12 +36,12 @@ ENV \
     AR_aarch64_unknown_fuchsia=aarch64-unknown-fuchsia-ar \
     CC_aarch64_unknown_fuchsia=aarch64-unknown-fuchsia-clang \
     CXX_aarch64_unknown_fuchsia=aarch64-unknown-fuchsia-clang++ \
-    AR_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-ar \
-    CC_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-gcc \
-    CXX_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-g++ \
-    AR_x86_64_sun_solaris=x86_64-sun-solaris2.11-ar \
-    CC_x86_64_sun_solaris=x86_64-sun-solaris2.11-gcc \
-    CXX_x86_64_sun_solaris=x86_64-sun-solaris2.11-g++
+    AR_sparcv9_sun_solaris=sparcv9-sun-solaris2.10-ar \
+    CC_sparcv9_sun_solaris=sparcv9-sun-solaris2.10-gcc \
+    CXX_sparcv9_sun_solaris=sparcv9-sun-solaris2.10-g++ \
+    AR_x86_64_sun_solaris=x86_64-sun-solaris2.10-ar \
+    CC_x86_64_sun_solaris=x86_64-sun-solaris2.10-gcc \
+    CXX_x86_64_sun_solaris=x86_64-sun-solaris2.10-g++
 
 ENV TARGETS=x86_64-unknown-fuchsia
 ENV TARGETS=$TARGETS,aarch64-unknown-fuchsia
diff --git a/src/ci/docker/cross2/build-solaris-toolchain.sh b/src/ci/docker/cross2/build-solaris-toolchain.sh
index ae84cc62b60..935cbe5d61b 100755
--- a/src/ci/docker/cross2/build-solaris-toolchain.sh
+++ b/src/ci/docker/cross2/build-solaris-toolchain.sh
@@ -25,7 +25,7 @@ cd binutils
 curl https://ftp.gnu.org/gnu/binutils/binutils-$BINUTILS.tar.xz | tar xJf -
 mkdir binutils-build
 cd binutils-build
-hide_output ../binutils-$BINUTILS/configure --target=$ARCH-sun-solaris2.11
+hide_output ../binutils-$BINUTILS/configure --target=$ARCH-sun-solaris2.10
 hide_output make -j10
 hide_output make install
 
@@ -58,13 +58,17 @@ for deb in *$APT_ARCH.deb; do
   dpkg -x $deb .
 done
 
-mkdir                  /usr/local/$ARCH-sun-solaris2.11/usr
-mv usr/include         /usr/local/$ARCH-sun-solaris2.11/usr/include
-mv usr/lib/$LIB_ARCH/* /usr/local/$ARCH-sun-solaris2.11/lib
-mv     lib/$LIB_ARCH/* /usr/local/$ARCH-sun-solaris2.11/lib
+# Strip Solaris 11 functions that are optionally used by libbacktrace.
+# This is for Solaris 10 compatibility.
+$ARCH-sun-solaris2.10-strip -N dl_iterate_phdr -N strnlen lib/$LIB_ARCH/libc.so
 
-ln -s /usr/local/$ARCH-sun-solaris2.11/usr/include /usr/local/$ARCH-sun-solaris2.11/sys-include
-ln -s /usr/local/$ARCH-sun-solaris2.11/usr/include /usr/local/$ARCH-sun-solaris2.11/include
+mkdir                  /usr/local/$ARCH-sun-solaris2.10/usr
+mv usr/include         /usr/local/$ARCH-sun-solaris2.10/usr/include
+mv usr/lib/$LIB_ARCH/* /usr/local/$ARCH-sun-solaris2.10/lib
+mv     lib/$LIB_ARCH/* /usr/local/$ARCH-sun-solaris2.10/lib
+
+ln -s /usr/local/$ARCH-sun-solaris2.10/usr/include /usr/local/$ARCH-sun-solaris2.10/sys-include
+ln -s /usr/local/$ARCH-sun-solaris2.10/usr/include /usr/local/$ARCH-sun-solaris2.10/include
 
 cd ..
 rm -rf solaris
@@ -80,7 +84,7 @@ mkdir ../gcc-build
 cd ../gcc-build
 hide_output ../gcc-$GCC/configure \
   --enable-languages=c,c++        \
-  --target=$ARCH-sun-solaris2.11  \
+  --target=$ARCH-sun-solaris2.10  \
   --with-gnu-as                   \
   --with-gnu-ld                   \
   --disable-multilib              \
@@ -94,7 +98,7 @@ hide_output ../gcc-$GCC/configure \
   --disable-libsanitizer          \
   --disable-libquadmath-support   \
   --disable-lto                   \
-  --with-sysroot=/usr/local/$ARCH-sun-solaris2.11
+  --with-sysroot=/usr/local/$ARCH-sun-solaris2.10
 
 hide_output make -j10
 hide_output make install