dump configure errors if configure fails

nginx.spec

@@ -203,7 +203,9 @@ sed -i -e 's#PROFILE=SYSTEM#HIGH:!aNULL:!MD5#' nginx.conf
 # to error out.  This is is also the reason for the DESTDIR environment
 # variable.
 export DESTDIR=%{buildroot}
-./configure \
+# So the perl module finds its symbols:
+nginx_ldopts="$RPM_LD_FLAGS -Wl,-E"
+if ! ./configure \
     --prefix=%{_datadir}/nginx \
     --sbin-path=%{_sbindir}/nginx \
     --modules-path=%{_libdir}/nginx/modules \
@@ -254,7 +256,11 @@ export DESTDIR=%{buildroot}
 %endif
     --with-debug \
     --with-cc-opt="%{optflags} $(pcre-config --cflags)" \
-    --with-ld-opt="$RPM_LD_FLAGS -Wl,-E" # so the perl module finds its symbols
+    --with-ld-opt="$nginx_ldopts"; then
+  : configure failed
+  cat objs/autoconf.err
+  exit 1
+fi
 
 make %{?_smp_mflags}