commit c12734230f00b338e22d94c8dda9a66af32b737e
Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date:   Tue Mar 25 20:40:05 2025 +0100

    focuspoll: Force c++11 standard only when needed
    
    We need at least c++11 to get unique_ptr, but we can thus not force using
    c++11 any more nowadays, otherwise we get
    
    In file included from /usr/include/unicode/uenum.h:25,
                     from /usr/include/unicode/ucnv.h:52,
                     from /usr/include/libxml2/libxml/encoding.h:31,
                     from /usr/include/libxml2/libxml/parser.h:812,
                     from /usr/include/compiz/compiz.h:29,
                     from /usr/include/compiz/compiz-plugin.h:29,
                     from /usr/include/compiz/compiz-core.h:29,
                     from focuspoll.cpp:36:
    /usr/include/unicode/localpointer.h:561:26: error: parameter declared 'auto'
      561 | template <typename Type, auto closeFunction>
          |                          ^~~~
    
    Because icu started requiring c++17 in its version 76.
    
    Leaving this empty makes gcc >= 11 assume c++17, and should fare fine on the
    long run. To avoid breaking building with gcc 10 and earlier which does not
    default to c++>=11, we can use ‘ac_prog_cxx_stdcxx’ to detect when
    -std=c++11 is needed.

diff --git a/configure.ac b/configure.ac
index 0860d99..fc61e6c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -82,6 +82,11 @@ if test "x$GCC" = "xyes"; then
   fi
 fi
 
+if test "$ac_prog_cxx_stdcxx" = "cxx98"; then
+  # Old gcc, we need to enable C++11 explicitly
+  CPPFLAGS="-std=c++11"
+fi
+
 AC_C_BIGENDIAN
 
 plugindir=$libdir/compiz
diff --git a/src/focuspoll/Makefile.am b/src/focuspoll/Makefile.am
index 16ec6c5..199acb0 100644
--- a/src/focuspoll/Makefile.am
+++ b/src/focuspoll/Makefile.am
@@ -16,8 +16,6 @@ AM_CPPFLAGS =                              \
 	-DLOCALEDIR="\"@datadir@/locale\""  \
 	-DIMAGEDIR='"$(imagedir)"'
 
-AM_CXXFLAGS = -std=c++11
-
 moduledir = $(plugindir)
 
 if FOCUSPOLL_PLUGIN
