libmicrohttpd2

commit eb200338a0fc1d1a23147bf3633c776cca700019
parent 08a76b6bd65390c60c370941c2ce3450ba00e06b
Author: Evgeny Grin (Karlson2k) <k2k@drgrin.dev>
Date:   Tue,  7 Oct 2025 21:20:43 +0200

configure: added check for enums with fixed base type

Diffstat:
M
configure.ac
 | 
32
++++++++++++++++++++++++++++++++
M
src/incl_priv/mhd_sys_options.h
 | 
11
+++++++++++

2 files changed, 43 insertions(+), 0 deletions(-)
diff --git a/configure.ac b/configure.ac
@@ -1277,6 +1277,38 @@ AC_CACHE_CHECK([whether $CC supports trailing comma in enum],[mhd_cv_enum_traili
 AS_VAR_IF([mhd_cv_enum_trailing_comma],["yes"],[],
   [AC_DEFINE([MHD_ENUMS_NEED_TRAILING_VALUE],[1],[Define to '1' if your compiler does not support enum with trailing comma])]
 )
+AC_CACHE_CHECK([whether $CC supports enum fixed underlying type],[mhd_cv_enum_base_type],
+  [
+    AC_COMPILE_IFELSE(
+      [AC_LANG_SOURCE([[enum TestEnum : unsigned char {ENM_VAL_A, ENM_VAL_B};]])],
+      [mhd_cv_enum_base_type="yes"],
+      [
+        mhd_cv_enum_base_type="no"
+        mhd_cv_enum_base_type_warnless="no"
+      ]
+    )
+  ]
+)
+AS_VAR_IF([mhd_cv_enum_base_type],["yes"],
+  [
+    AC_DEFINE([HAVE_ENUM_BASE_TYPE],[1],[Define to '1' if your compiler supports enum with fixed underlying type])
+    AC_CACHE_CHECK([whether enum fixed underlying type works without warnings],[mhd_cv_enum_base_type_warnless],
+      [
+        SAVE_c_werror_flag="$ac_c_werror_flag"
+        ac_c_werror_flag="yes"
+        AC_COMPILE_IFELSE(
+          [AC_LANG_SOURCE([[enum TestEnum : unsigned char {ENM_VAL_A, ENM_VAL_B};]])],
+          [mhd_cv_enum_base_type_warnless="yes"],
+          [mhd_cv_enum_base_type_warnless="no"]
+        )
+        ac_c_werror_flag="$SAVE_c_werror_flag"
+      ]
+    )
+    AS_VAR_IF([mhd_cv_enum_base_type_warnless],["yes"],
+      [AC_DEFINE([HAVE_ENUM_BASE_TYPE_WARNLESS],[1],[Define to '1' if your compiler supports enum with fixed underlying type without warnings])]
+    )
+  ]
+)
 
 
 AS_VAR_SET_IF([ac_cv_c_restrict],[],
diff --git a/src/incl_priv/mhd_sys_options.h b/src/incl_priv/mhd_sys_options.h
@@ -368,6 +368,16 @@
 #  define MHD_FIXED_FLAGS_ENUM_MHD_APP_SET_ MHD_FLAGS_ENUM_ /* enum can be extended in next MHD versions */
 #endif
 
+// TODO: support warnings mute
+#ifdef HAVE_ENUM_BASE_TYPE_WARNLESS
+#  define mhd_USE_ENUM_BASE_T   1
+#endif
+#ifdef mhd_USE_ENUM_BASE_T
+#  define mhd_ENUM_BASE_T(fixed_type) : fixed_type
+#else
+#  define mhd_ENUM_BASE_T(fixed_type) /* empty */
+#endif
+
 /**
  * Automatic string with the name of the current function
  */
@@ -643,6 +653,7 @@
 #      define HAVE_STDBOOL_H    1
 #    endif
 #  endif
+#  define mhd_ENUM_BASE_T(base) /* nothing */
 #  if ((__STDC_VERSION__ + 0) >= 202311)
 #    define alignof _Alignof
 #  endif