Re: AC_C_INLINE with -Werror llvm 3.4

[Kurt Schwehr]

Yes.  My patch is indeed missing a ().

> Are't you missing () there to actually call the function?
>
> --
> VZ

git diff
diff --git a/lib/autoconf/c.m4 b/lib/autoconf/c.m4
index b58e42d..74c6aa8 100644
--- a/lib/autoconf/c.m4
+++ b/lib/autoconf/c.m4
@@ -1742,7 +1742,7 @@ for ac_kw in inline __inline__ __inline; do
 [#ifndef __cplusplus
 typedef int foo_t;
 static $ac_kw foo_t static_foo () {return 0; }
-$ac_kw foo_t foo () {return 0; }
+$ac_kw foo_t foo () {return static_foo(); }
 #endif
 ])],
                    [ac_cv_c_inline=$ac_kw])


On Sun, Jun 8, 2014 at 9:25 AM, Kurt Schwehr <address@hidden> wrote:

> I'm trying to clean hdf5 1.9.182 a bit and I'm using -Werror as my first
> pass tool.  Just cleaning the messages that come up.  However, passing
> -Werror as CPPFLAGS causes configure to die on a number of places.  Here is
> a first one with a proposed fix.  The AC_C_INLINE macro tries to compile an
> inline function, but doesn't use it.  Why not just make the return 0 be
> returning the zero from the static_foo inline function to insure that it's
> used?
>
> git diff
> diff --git a/lib/autoconf/c.m4 b/lib/autoconf/c.m4
> index b58e42d..6779407 100644
> --- a/lib/autoconf/c.m4
> +++ b/lib/autoconf/c.m4
> @@ -1742,7 +1742,7 @@ for ac_kw in inline __inline__ __inline; do
>  [#ifndef __cplusplus
>  typedef int foo_t;
>  static $ac_kw foo_t static_foo () {return 0; }
> -$ac_kw foo_t foo () {return 0; }
> +$ac_kw foo_t foo () {return static_foo; }
>  #endif
>  ])],
>                     [ac_cv_c_inline=$ac_kw])
>
>
> Found via:
>
>
> ftp://ftp.hdfgroup.uiuc.edu/pub/outgoing/hdf5/snapshots/v19/hdf5-1.9.182.tar.bz2
>
> tar xf hdf5-1.9.182.tar.bz2
> mkdir build && cd build
> CPPFLAGS="-Werror -Wall -Wextra" ../hdf5-1.9.182/configure --enable-shared
> --enable-cxx --with-zlib=/usr --without-mpe --with-szlib=/sw
> --without-pthread --disable-parallel --enable-build-all
> --enable-maintainer-mode --enable-codestack --enable-debug=all
> --disable-silent-rules
>
> This file contains any messages produced by compilers while
> running configure, to aid debugging if configure makes a mistake.
>
> It was created by HDF5 configure 1.9.182, which was
> generated by GNU Autoconf 2.69.  Invocation command line was
>
>   $ ../hdf5-1.9.182/configure --enable-shared --enable-cxx
> --with-zlib=/usr --without-mpe --with-szlib=/sw --without-pthread
> --disable-parallel --enable-build-all --enable-maintainer-mode
> --enable-codestack --enable-debug=all --disable-silent-rules
>
>
> configure:27495: clang -c          -Werror=unused-variable -Wall -Wextra
> -I/sw/include conftest.c >&5
> configure:27495: $? = 0
> configure:27502: result: yes
> configure:27510: checking for inline
> configure:27526: clang -c          -Werror=unused-variable -Wall -Wextra
> -I/sw/include conftest.c >&5
> conftest.c:132:21: warning: unused function 'static_foo'
> [-Wunused-function]
> static inline foo_t static_foo () {return 0; }
>                     ^
> 1 warning generated.
> configure:27526: $? = 0
> configure:27534: result: inline
>
>
> configure.ac has:
>
> ## ----------------------------------------------------------------------
> ## Check compiler characteristics
> ##
> AC_C_CONST
> AC_C_INLINE
>
>
> clang --version
> Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
> Target: x86_64-apple-darwin13.2.0
> Thread model: posix
>
> xcodebuild -version
> Xcode 5.1.1
> Build version 5B1008
>
> uname -a
> Darwin schwehr-macbookpro 13.2.0 Darwin Kernel Version 13.2.0: Thu Apr 17
> 23:03:13 PDT 2014; root:xnu-2422.100.13~1/RELEASE_X86_64 x86_64
>



-- 
--
http://schwehr.org