When building a testdir of all of gnulib with GCC 10.1.0, I see these
compilation errors:
In file included from ../../gltests/test-list-c++.cc:23:
../gllib/string.h:806:1: error: type of 'strchr' is unknown
806 | _GL_WARN_ON_USE (strchr, "strchr cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
../gllib/string.h:806:1: error: 'int strchr' redeclared as different kind of
entity
806 | _GL_WARN_ON_USE (strchr, "strchr cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
In file included from ../gllib/string.h:41,
from ../../gltests/test-list-c++.cc:23:
/usr/include/string.h:224:1: note: previous declaration 'const char*
strchr(const char*, int)'
224 | strchr (const char *__s, int __c) __THROW
| ^~~~~~
In file included from ../../gltests/test-list-c++.cc:23:
../gllib/string.h:1000:1: error: type of 'strpbrk' is unknown
1000 | _GL_WARN_ON_USE (strpbrk, "strpbrk cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
../gllib/string.h:1000:1: error: 'int strpbrk' redeclared as different kind of
entity
1000 | _GL_WARN_ON_USE (strpbrk, "strpbrk cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
In file included from ../gllib/string.h:41,
from ../../gltests/test-list-c++.cc:23:
/usr/include/string.h:303:1: note: previous declaration 'const char*
strpbrk(const char*, const char*)'
303 | strpbrk (const char *__s, const char *__accept) __THROW
| ^~~~~~~
In file included from ../../gltests/test-list-c++.cc:23:
../gllib/string.h:1027:1: error: type of 'strrchr' is unknown
1027 | _GL_WARN_ON_USE (strrchr, "strrchr cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
../gllib/string.h:1027:1: error: 'int strrchr' redeclared as different kind of
entity
1027 | _GL_WARN_ON_USE (strrchr, "strrchr cannot work correctly on character
strings "
| ^~~~~~~~~~~~~~~
In file included from ../gllib/string.h:41,
from ../../gltests/test-list-c++.cc:23:
/usr/include/string.h:251:1: note: previous declaration 'const char*
strrchr(const char*, int)'
251 | strrchr (const char *__s, int __c) __THROW
| ^~~~~~~
This patch fixes it.
2020-05-10 Bruno Haible <br...@clisp.org>
string: Fix compilation error in C++ mode.
* lib/warn-on-use.h (_GL_WARN_ON_USE_CXX): In C mode, use plain
_GL_WARN_ON_USE.
* lib/string.in.h (strchr, strpbrk, strrchr): Use _GL_WARN_ON_USE_CXX
instead of _GL_WARN_ON_USE.
diff --git a/lib/string.in.h b/lib/string.in.h
index d601450..77ccf94 100644
--- a/lib/string.in.h
+++ b/lib/string.in.h
@@ -334,9 +334,10 @@ _GL_WARN_ON_USE (stpncpy, "stpncpy is unportable - "
GB18030 and the character to be searched is a digit. */
# undef strchr
/* Assume strchr is always declared. */
-_GL_WARN_ON_USE (strchr, "strchr cannot work correctly on character strings "
- "in some multibyte locales - "
- "use mbschr if you care about internationalization");
+_GL_WARN_ON_USE_CXX (strchr, const char *, (const char *, int),
+ "strchr cannot work correctly on character strings "
+ "in some multibyte locales - "
+ "use mbschr if you care about internationalization");
#endif
/* Find the first occurrence of C in S or the final NUL byte. */
@@ -528,15 +529,17 @@ _GL_CXXALIASWARN (strpbrk);
locale encoding is GB18030 and one of the characters to be searched is a
digit. */
# undef strpbrk
-_GL_WARN_ON_USE (strpbrk, "strpbrk cannot work correctly on character strings "
- "in multibyte locales - "
- "use mbspbrk if you care about internationalization");
+_GL_WARN_ON_USE_CXX (strpbrk, const char *, (const char *, const char *),
+ "strpbrk cannot work correctly on character strings "
+ "in multibyte locales - "
+ "use mbspbrk if you care about internationalization");
# endif
#elif defined GNULIB_POSIXCHECK
# undef strpbrk
# if HAVE_RAW_DECL_STRPBRK
-_GL_WARN_ON_USE (strpbrk, "strpbrk is unportable - "
- "use gnulib module strpbrk for portability");
+_GL_WARN_ON_USE_CXX (strpbrk, const char *, (const char *, const char *),
+ "strpbrk is unportable - "
+ "use gnulib module strpbrk for portability");
# endif
#endif
@@ -555,9 +558,10 @@ _GL_WARN_ON_USE (strspn, "strspn cannot work correctly on
character strings "
GB18030 and the character to be searched is a digit. */
# undef strrchr
/* Assume strrchr is always declared. */
-_GL_WARN_ON_USE (strrchr, "strrchr cannot work correctly on character strings "
- "in some multibyte locales - "
- "use mbsrchr if you care about internationalization");
+_GL_WARN_ON_USE_CXX (strrchr, const char *, (const char *, int),
+ "strrchr cannot work correctly on character strings "
+ "in some multibyte locales - "
+ "use mbsrchr if you care about internationalization");
#endif
/* Search the next delimiter (char listed in DELIM) starting at *STRINGP.
diff --git a/lib/warn-on-use.h b/lib/warn-on-use.h
index 1cf5770..291e709 100644
--- a/lib/warn-on-use.h
+++ b/lib/warn-on-use.h
@@ -100,23 +100,28 @@ _GL_WARN_EXTERN_C int _gl_warn_on_use
#endif
/* _GL_WARN_ON_USE_CXX (function, rettype, parameters_and_attributes, "string")
- is like _GL_WARN_ON_USE (function, "string"), except that the function is
- declared with the given prototype, consisting of return type, parameters,
- and attributes.
+ is like _GL_WARN_ON_USE (function, "string"), except that in C++ mode the
+ function is declared with the given prototype, consisting of return type,
+ parameters, and attributes.
This variant is useful for overloaded functions in C++. _GL_WARN_ON_USE does
not work in this case. */
#ifndef _GL_WARN_ON_USE_CXX
-# if 4 < __GNUC__ || (__GNUC__ == 4 && 3 <= __GNUC_MINOR__)
+# if !defined __cplusplus
# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
+ _GL_WARN_ON_USE (function, msg)
+# else
+# if 4 < __GNUC__ || (__GNUC__ == 4 && 3 <= __GNUC_MINOR__)
+# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg)
\
extern rettype function parameters_and_attributes \
__attribute__ ((__warning__ (msg)))
-# elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING
+# elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING
/* Verify the existence of the function. */
-# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
+# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg)
\
extern rettype function parameters_and_attributes
-# else /* Unsupported. */
-# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg) \
+# else /* Unsupported. */
+# define _GL_WARN_ON_USE_CXX(function,rettype,parameters_and_attributes,msg)
\
_GL_WARN_EXTERN_C int _gl_warn_on_use
+# endif
# endif
#endif
