curl_setup.h: detect 'inline' support

Closes #13355

configure.ac

@@ -497,9 +497,6 @@ fi
 AC_SUBST(REQUIRE_LIB_DEPS)
 AM_CONDITIONAL(USE_EXPLICIT_LIB_DEPS, test x$REQUIRE_LIB_DEPS = xyes)
 
-dnl check if there's a way to force code inline
-AC_C_INLINE
-
 dnl **********************************************************************
 dnl platform/compiler/architecture specific checks/flags
 dnl **********************************************************************

lib/curl_config.h.cmake

@@ -776,12 +776,6 @@ ${SIZEOF_TIME_T_CODE}
 /* Type to use in place of in_addr_t when system does not provide it. */
 #cmakedefine in_addr_t ${in_addr_t}
 
-/* Define to `__inline__' or `__inline' if that's what the C compiler
- calls it, or to nothing if 'inline' is not supported under any name. */
-#ifndef __cplusplus
-#undef inline
-#endif
-
 /* Define to `unsigned int' if <sys/types.h> does not define. */
 #cmakedefine size_t ${size_t}
 

lib/curl_setup.h

@@ -891,4 +891,26 @@ int getpwuid_r(uid_t uid, struct passwd *pwd, char *buf,
 #define OPENSSL_SUPPRESS_DEPRECATED
 #endif
 
+#if defined(inline)
+ /* 'inline' is defined as macro and assumed to be correct */
+ /* No need for 'inline' replacement */
+#elif defined(__cplusplus)
+ /* The code is compiled with C++ compiler.
+ C++ always supports 'inline'. */
+ /* No need for 'inline' replacement */
+#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901
+ /* C99 (and later) supports 'inline' keyword */
+ /* No need for 'inline' replacement */
+#elif defined(__GNUC__) && __GNUC__ >= 3
+ /* GCC supports '__inline__' as an extension */
+# define inline __inline__
+#elif defined(_MSC_VER) && _MSC_VER >= 1400
+ /* MSC supports '__inline' from VS 2005 (or even earlier) */
+# define inline __inline
+#else
+ /* Probably 'inline' is not supported by compiler.
+ Define to the empty string to be on the safe side. */
+# define inline /* empty */
+#endif
+
 #endif /* HEADER_CURL_SETUP_H */

lib/curl_sha512_256.c

@@ -286,29 +286,13 @@ Curl_sha512_256_finish(unsigned char *digest,
  defined(_MSC_VER) && !defined(__GNUC__) && !defined(__clang__)
 # if _MSC_VER >= 1400
 # define MHDX_INLINE __forceinline
-# else
-# define MHDX_INLINE /* empty */
 # endif
 #endif
 
 #if !defined(MHDX_INLINE)
-# if defined(inline)
- /* Assume that 'inline' macro was already defined correctly by
- * the build system. */
-# define MHDX_INLINE inline
-# elif defined(__cplusplus)
- /* The code is compiled with C++ compiler.
- * C++ always supports 'inline'. */
-# define MHDX_INLINE inline
-# elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901
- /* C99 (and later) supports 'inline' keyword */
-# define MHDX_INLINE inline
-# elif defined(__GNUC__) && __GNUC__ >= 3
- /* GCC supports '__inline__' as an extension */
-# define MHDX_INLINE __inline__
-# else
-# define MHDX_INLINE /* empty */
-# endif
+ /* Assume that 'inline' keyword works or the
+ * macro was already defined correctly. */
+# define MHDX_INLINE inline
 #endif
 
 /* Bits manipulation macros and functions.