fix(system): rename __VA_NARG__ macro

__VA_NARG__ is copied from a forum post and is a pretty common implementation
with a high chance of causing naming collision

Added ESP_ namespace to avoid this.

components/esp_common/include/esp_macros.h

@@ -50,15 +50,15 @@ extern "C" {
 /* Count number of arguments of __VA_ARGS__
  * - reference https://groups.google.com/forum/#!topic/comp.std.c/d-6Mj5Lko_s
  * - __GET_NTH_ARG__() takes args >= N (64) but only expand to Nth one (64th)
- * - __RSEQ_N__() is reverse sequential to N to add padding to have Nth
+ * - ESP_RSEQ_N() is reverse sequential to N to add padding to have Nth
  *   position is the same as the number of arguments
  * - ##__VA_ARGS__ is used to deal with 0 parameter (swallows comma)
  */
-#ifndef __VA_NARG__
+#ifndef ESP_VA_NARG
-# define __VA_NARG__(...)   __NARG__(_0, ##__VA_ARGS__, __RSEQ_N__())
+# define ESP_VA_NARG(...)   ESP_NARG(_0, ##__VA_ARGS__, ESP_RSEQ_N())
 
-# define __NARG__(...)      __GET_NTH_ARG__(__VA_ARGS__)
+# define ESP_NARG(...)      ESP_GET_NTH_ARG(__VA_ARGS__)
-# define __GET_NTH_ARG__( \
+# define ESP_GET_NTH_ARG( \
         _01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \
         _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
         _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
@@ -66,7 +66,7 @@ extern "C" {
         _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \
         _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \
         _61,_62,_63,N,...) N
-# define __RSEQ_N__() \
+# define ESP_RSEQ_N() \
         62,61,60,                      \
         59,58,57,56,55,54,53,52,51,50, \
         49,48,47,46,45,44,43,42,41,40, \
@@ -80,25 +80,6 @@ extern "C" {
 #define ESP_UNUSED(x) ((void)(x))
 #endif
 
-/* test macros */
-#define foo_args(...) 1
-#define foo_no_args() 2
-#if defined(__cplusplus) && (__cplusplus >  201703L)
-#define foo(...) CHOOSE_MACRO_VA_ARG(foo_args, foo_no_args __VA_OPT__(,) __VA_ARGS__)(__VA_ARGS__)
-#else
-#define foo(...) CHOOSE_MACRO_VA_ARG(foo_args, foo_no_args, ##__VA_ARGS__)(__VA_ARGS__)
-#endif
-
-ESP_STATIC_ASSERT(foo() == 2, "CHOOSE_MACRO_VA_ARG() result does not match for 0 arguments");
-ESP_STATIC_ASSERT(foo(42) == 1, "CHOOSE_MACRO_VA_ARG() result does not match for 1 argument");
-#if defined(__cplusplus) && (__cplusplus >  201703L)
-ESP_STATIC_ASSERT(foo(42, 87) == 1, "CHOOSE_MACRO_VA_ARG() result does not match for n arguments");
-#endif
-
-#undef foo
-#undef foo_args
-#undef foo_no_args
-
 #define ESP_INFINITE_LOOP() \
     do { \
         ESP_COMPILER_DIAGNOSTIC_PUSH_IGNORE("-Wanalyzer-infinite-loop") \

components/esp_common/test_apps/esp_common/main/CMakeLists.txt

@@ -1,4 +1,4 @@
-idf_component_register(SRCS "test_app_main.c" "test_attr.c"
+idf_component_register(SRCS "test_app_main.c" "test_attr.c" "test_esp_macro.c"
                        INCLUDE_DIRS "."
                        PRIV_REQUIRES unity esp_mm esp_psram
                        WHOLE_ARCHIVE)

components/esp_common/test_apps/esp_common/main/test_esp_macro.c

@@ -0,0 +1,21 @@
+/*
+ * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include "esp_macros.h"
+
+/* test macros */
+#define foo_args(...) 1
+#define foo_no_args() 2
+#if defined(__cplusplus) && (__cplusplus >  201703L)
+#define foo(...) CHOOSE_MACRO_VA_ARG(foo_args, foo_no_args __VA_OPT__(,) __VA_ARGS__)(__VA_ARGS__)
+#else
+#define foo(...) CHOOSE_MACRO_VA_ARG(foo_args, foo_no_args, ##__VA_ARGS__)(__VA_ARGS__)
+#endif
+
+ESP_STATIC_ASSERT(foo() == 2, "CHOOSE_MACRO_VA_ARG() result does not match for 0 arguments");
+ESP_STATIC_ASSERT(foo(42) == 1, "CHOOSE_MACRO_VA_ARG() result does not match for 1 argument");
+#if defined(__cplusplus) && (__cplusplus >  201703L)
+ESP_STATIC_ASSERT(foo(42, 87) == 1, "CHOOSE_MACRO_VA_ARG() result does not match for n arguments");
+#endif

components/esp_hw_support/include/esp_private/esp_regdma.h

@@ -396,9 +396,9 @@ void *regdma_find_prev_module_link_tail(void *link, void *tail, int entry, uint3
  */
 void *regdma_find_next_module_link_head(void *link, void *tail, int entry, uint32_t module);
 
-#define regdma_link_init_safe(pcfg, branch, module, ...)    regdma_link_init((pcfg), (branch), (module), __VA_NARG__(__VA_ARGS__), ##__VA_ARGS__)
+#define regdma_link_init_safe(pcfg, branch, module, ...)    regdma_link_init((pcfg), (branch), (module), ESP_VA_NARG(__VA_ARGS__), ##__VA_ARGS__)
 
-#define regdma_link_update_next_safe(link, ...)             regdma_link_update_next((link), __VA_NARG__(__VA_ARGS__), ##__VA_ARGS__)
+#define regdma_link_update_next_safe(link, ...)             regdma_link_update_next((link), ESP_VA_NARG(__VA_ARGS__), ##__VA_ARGS__)
 
 #endif // SOC_PAU_SUPPORTED
 

docs/en/migration-guides/release-5.x/5.4/system.rst

@@ -3,6 +3,11 @@ System
 
 :link_to_translation:`zh_CN:[中文]`
 
+ESP-Common
+----------
+
+``__VA_NARG__`` and its related macros have been re-named to avoid naming collisions, use the new name with ``ESP`` pre-fix, e.g. ``ESP_VA_NARG`` instead.
+
 Log
 ---
 

docs/zh_CN/migration-guides/release-5.x/5.4/system.rst

@@ -3,6 +3,11 @@
 
 :link_to_translation:`en:[English]`
 
+ESP-Common
+----------
+
+``__VA_NARG__`` 及其相关宏已被重新命名以避免命名冲突，请使用带有 ESP 前缀的新名称，例如 ``ESP_VA_NARG``。
+
 日志
 ------
 

tools/idf_py_actions/hints.yml

@@ -447,3 +447,6 @@
 -
     re: "(error: Total discarded sections size is \\d+ bytes)|(region [`'.\\w]+ overflowed by \\d+ bytes)"
     hint: "The binary size has exceeded the limit. To resolve the issue consider reducing the binary size.\nYou can explore size optimization techniques in the documentation by running 'idf.py docs -sp api-guides/performance/size.html#reducing-overall-size'.\nNote that the linker performed the dead code elimination."
+
+    re: "implicit declaration of function '__VA_NARG__'"
+    hint: "__VA_NARG_ has been renamed. Please use ESP_VA_NARG instead"