Merge pull request #123 from nataraj-hates-MS-for-stealing-github/main

HexDecimal · web-flow · commit f9c2d9dcc9a7 · 2022-07-29T13:29:11.000-07:00
Fix building with gcc 8.3 (need to link stdc++fs for that) Closes #122
diff --git a/buildsys/autotools/Makefile.am b/buildsys/autotools/Makefile.am
@@ -15,7 +15,7 @@ AM_CFLAGS = \
 
 AM_CPPFLAGS = $(AM_CFLAGS)
 
-AM_LDFLAGS = $(SDL_LIBS) $(X11_LIBS) $(ZLIB_LIBS)
+AM_LDFLAGS = $(SDL_LIBS) $(X11_LIBS) $(ZLIB_LIBS) $(SYSLIBS)
 
 
 lib_LTLIBRARIES = libtcod.la
diff --git a/buildsys/autotools/configure.ac b/buildsys/autotools/configure.ac
@@ -53,5 +53,30 @@ AC_SUBST([SOVERSION], [m4_esyscmd_s(./get_version.py --so)])
 
 AX_CXX_COMPILE_STDCXX([17], [noext], [mandatory])
 
+# In older versions of gcc implementation of std::filesystem is kept
+# in separate stdc++fs library. You should link it explicitly
+AC_LANG_SAVE
+AC_LANG([C++])
+AC_MSG_CHECKING([if std::filesystem requires linking stdc++fs])
+AC_LINK_IFELSE(
+    [AC_LANG_SOURCE([
+        #include <filesystem>
+        int main() {
+            std::filesystem::create_directory("/dev/null");
+        }
+    ])],
+    [ac_cv_fs_stdlib=no],
+    [ac_cv_fs_stdlib=yes]
+)
+if test "x$ac_cv_fs_stdlib" = xyes; then
+    AC_MSG_RESULT(yes)
+    SYSLIBS="$SYSLIBS -lstdc++fs"
+else
+    AC_MSG_RESULT(no)
+fi
+AC_LANG_RESTORE
+
+AC_SUBST(SYSLIBS)
+
 AC_CONFIG_FILES([Makefile libtcod.pc])
 AC_OUTPUT
