include: avoid recursive macros

To fix potential `-Wdisabled-macro-expansion` warnings when using these
macros within other macros. Fixing for example:
```
lib/doh.c:328:3: error: disabled expansion of recursive macro [clang-diagnostic-disabled-macro-expansion,-warnings-as-errors]
  328 |   ERROR_CHECK_SETOPT(CURLOPT_URL, url);
      |   ^
lib/doh.c:271:14: note: expanded from macro 'ERROR_CHECK_SETOPT'
  271 |     result = curl_easy_setopt((CURL *)doh, x, y);       \
      |              ^
include/curl/curl.h:3332:44: note: expanded from macro 'curl_easy_setopt'
 3332 | #define curl_easy_setopt(handle,opt,param) curl_easy_setopt(handle,opt,param)
      |                                            ^
[...]
```

Also update comments on why curl continues to disable
`-Wdisabled-macro-expansion` and `-Wused-but-marked-unused` warnings.

Follow-up to 92f215fea1 #18477

Closes #20597

CMake/PickyWarnings.cmake

@@ -147,7 +147,7 @@ if(PICKY_COMPILER)
       list(APPEND _picky_enable
         ${_picky_common_old}
         -Wconditional-uninitialized        # clang  3.0
-        -Wno-used-but-marked-unused        # clang  3.0                         # Triggered by typecheck-gcc.h (with clang 14+)
+        -Wno-used-but-marked-unused        # clang  3.0            # Triggered by typecheck-gcc.h with clang 14+, dependency headers
         -Wshift-sign-overflow              # clang  2.9
         -Wshorten-64-to-32                 # clang  1.0
         -Wformat=2                         # clang  3.0  gcc  4.8
@@ -161,7 +161,7 @@ if(PICKY_COMPILER)
       if(CMAKE_C_COMPILER_VERSION VERSION_GREATER_EQUAL 3.1)
         list(APPEND _picky_enable
           -Wno-covered-switch-default      # clang  3.1            appleclang  3.1  # Annoying to fix or silence
-          -Wno-disabled-macro-expansion    # clang  3.1            appleclang  3.1  # Triggered by typecheck-gcc.h (with clang 14+)
+          -Wno-disabled-macro-expansion    # clang  3.1            appleclang  3.1  # Triggered by standard headers
         )
         if(MSVC)
           list(APPEND _picky_enable

include/curl/curl.h

@@ -3329,10 +3329,14 @@ CURL_EXTERN CURLcode curl_easy_ssls_export(CURL *handle,
 /* This preprocessor magic that replaces a call with the exact same call is
    only done to make sure application authors pass exactly three arguments
    to these functions. */
-#define curl_easy_setopt(handle,opt,param) curl_easy_setopt(handle,opt,param)
-#define curl_easy_getinfo(handle,info,arg) curl_easy_getinfo(handle,info,arg)
-#define curl_share_setopt(share,opt,param) curl_share_setopt(share,opt,param)
-#define curl_multi_setopt(handle,opt,param) curl_multi_setopt(handle,opt,param)
+#define curl_easy_setopt(handle, opt, param) \
+  (curl_easy_setopt)(handle, opt, param)
+#define curl_easy_getinfo(handle, info, arg) \
+  (curl_easy_getinfo)(handle, info, arg)
+#define curl_share_setopt(share, opt, param) \
+  (curl_share_setopt)(share, opt, param)
+#define curl_multi_setopt(handle,opt,param) \
+  (curl_multi_setopt)(handle, opt, param)
 #endif /* __STDC__ >= 1 */
 #endif /* gcc >= 4.3 && !__cplusplus && !CURL_DISABLE_TYPECHECK */
 

include/curl/typecheck-gcc.h

@@ -156,7 +156,7 @@
               Wcurl_easy_setopt_err_CURLSH();                           \
           )                                                             \
           }                                                             \
-      curl_easy_setopt(handle, option, value);                          \
+      (curl_easy_setopt)(handle, option, value);                        \
     })
 
 /* wraps curl_easy_getinfo() with type checking */
@@ -190,7 +190,7 @@
               Wcurl_easy_getinfo_err_curl_off_t();                      \
           )                                                             \
           }                                                             \
-      curl_easy_getinfo(handle, info, arg);                             \
+      (curl_easy_getinfo)(handle, info, arg);                           \
     })
 
 #define curl_multi_setopt(handle, option, value)                        \
@@ -221,7 +221,7 @@
           if(!curlcheck_multitimer_cb(value))                           \
             Wcurl_multi_setopt_err_timercb();                           \
       }                                                                 \
-      curl_multi_setopt(handle, option, value);                         \
+      (curl_multi_setopt)(handle, option, value);                       \
     })
 
 /* evaluates to true if the option takes a data argument to pass to a
@@ -262,7 +262,8 @@
 /*
  * For now, just make sure that the functions are called with three arguments
  */
-#define curl_share_setopt(share,opt,param) curl_share_setopt(share,opt,param)
+#define curl_share_setopt(share, opt, param) \
+  (curl_share_setopt)(share, opt, param)
 
 /* the actual warnings, triggered by calling the Wcurl_easy_setopt_err*
  * functions */

m4/curl-compilers.m4

@@ -862,13 +862,13 @@ AC_DEFUN([CURL_SET_COMPILER_WARNING_OPTS], [
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [conditional-uninitialized])
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [language-extension-token])
             tmp_CFLAGS="$tmp_CFLAGS -Wformat=2"
-            tmp_CFLAGS="$tmp_CFLAGS -Wno-used-but-marked-unused"    # Triggered by typecheck-gcc.h (with clang 14+)
+            tmp_CFLAGS="$tmp_CFLAGS -Wno-used-but-marked-unused"    # Triggered by typecheck-gcc.h with clang 14+, dependency headers
           fi
           dnl Only clang 3.1 or later
           if test "$compiler_num" -ge "301"; then
             CURL_ADD_COMPILER_WARNINGS([tmp_CFLAGS], [format-non-iso])
             tmp_CFLAGS="$tmp_CFLAGS -Wno-covered-switch-default"    # Annoying to fix or silence
-            tmp_CFLAGS="$tmp_CFLAGS -Wno-disabled-macro-expansion"  # Triggered by typecheck-gcc.h (with clang 14+)
+            tmp_CFLAGS="$tmp_CFLAGS -Wno-disabled-macro-expansion"  # Triggered by standard headers
           fi
           #
           dnl Only clang 3.2 or later