Make libidn2 build optional

.gitlab-ci.yml

@@ -114,7 +114,7 @@ stages:
     - test -w "${CCACHE_DIR}" && export PATH="/usr/lib/ccache:${PATH}"
 #    - ./autogen.sh
   script:
-    - ./configure --enable-developer --with-libtool --disable-static --with-atf=/usr --with-libidn2 "${EXTRA_CONFIGURE}"
+    - ./configure --enable-developer --with-libtool --disable-static --with-atf=/usr "${EXTRA_CONFIGURE}"
     - make -j${PARALLEL_JOBS_BUILD:-1} -k all V=1
   artifacts:
     expire_in: '1 hour'
@@ -196,7 +196,7 @@ build:centos:centos6:amd64:
   variables:
     CC: gcc
     CFLAGS: "-Wall -Wextra -O2 -g"
-    EXTRA_CONFIGURE: "--disable-warn-error"
+    EXTRA_CONFIGURE: "--with-libidn2 --disable-warn-error"
   <<: *centos_centos6_amd64_image
   <<: *build_job
 
@@ -204,6 +204,7 @@ build:centos:centos7:amd64:
   variables:
     CC: gcc
     CFLAGS: "-Wall -Wextra -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
   <<: *centos_centos7_amd64_image
   <<: *build_job
 
@@ -211,6 +212,7 @@ build:clang:debian:sid:amd64:
   variables:
     CC: clang-6.0
     CFLAGS: "-Wall -Wextra -Wenum-conversion -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
   <<: *debian_sid_amd64_image
   <<: *build_job
 
@@ -232,6 +234,7 @@ build:debian:sid:amd64:
   variables:
     CC: gcc
     CFLAGS: "-Wall -Wextra -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
   <<: *debian_sid_amd64_image
   <<: *build_job
 
@@ -239,6 +242,7 @@ build:clang:debian:sid:i386:
   variables:
     CC: clang-6.0
     CFLAGS: "-Wall -Wextra -Wenum-conversion -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
   <<: *debian_sid_i386_image
   <<: *build_job
 
@@ -246,6 +250,7 @@ build:debian:sid:i386:
   variables:
     CC: gcc
     CFLAGS: "-Wall -Wextra -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
   <<: *debian_sid_i386_image
   <<: *build_job