Bug 552370 – media-libs/devil-1.7.8-r2: build failure with gcc-5.1 due to use of "restrict" keyword in C++ code

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Jasen Borisov 2015-06-17 08:55:09 UTC]

Emerging media-libs/devil-1.7.8-r2 fails with a compile error from gcc:

In file included from ./../src-IL/src/il_exr.cpp:14:0:
./../src-IL/include/il_internal.h:230:54: error: expected ‘,’ or ‘...’ before ‘FileName’
 ILboolean ilIsValidBmp(ILconst_string CONST_RESTRICT FileName);



Reproducible: Always




build log: https://bpaste.net/show/8328cc5e16b4

----
emerge -pqv '=media-libs/devil-1.7.8-r2::gentoo':

[ebuild  N    ] media-libs/devil-1.7.8-r2  USE="X gif jpeg jpeg2k mng opengl png sdl tiff xpm -allegro -glut -nvtt -openexr -static-libs" CPU_FLAGS_X86="sse sse2 -sse3"

----
emerge --info '=media-libs/devil-1.7.8-r2::gentoo':

https://bpaste.net/show/ef5c0f4f0312

[Comment 1 Mike Gilbert 2015-06-20 22:21:31 UTC]

Attach your build log to the bug; patebins are not acceptable.

[Comment 2 Jasen Borisov 2015-06-21 08:05:43 UTC]

Created attachment 405456 [details]
build.log

[Comment 3 Jasen Borisov 2015-06-21 08:07:00 UTC]

Created attachment 405458 [details]
emerge --info output

[Comment 4 Jasen Borisov 2015-06-21 08:08:27 UTC]

Done, attached both the build.log and the emerge --info output.

Sorry for using a pastebin at first. This was my first time reporting a bug on the gentoo bugzilla. I didn't know.

[Comment 5 SpanKY 2015-06-24 14:52:56 UTC]

i'd guess a bug in devil.  the error message indicates CONST_RESTIRCT isn't being defined and that's something devil itself sets up.

[Comment 6 Mr. Bones. (RETIRED) 2015-06-25 03:36:51 UTC]

I was hoping for some direction about the change in behavior between gcc4 and gcc5 since devil builds fine with current stable gcc4.

The line that's erroring is:

ILboolean ilIsValidBmp(ILconst_string CONST_RESTRICT FileName);

and CONST_RESTRICT is defined as const restrict
and ILconst_string is defined as wchar_t const *
so...  doesn't like wchar_t const * const restrict FileName now?

[Comment 7 SpanKY 2015-07-06 09:18:31 UTC]

(In reply to Mr. Bones. from comment #6)

then you want the gcc-porting@ alias ;)

the problem is that the devil configure script tests for the "restrict" keyword using the C frontend.  in C99, this keyword was added to C.  however, C++ has no such keyword, and the header uses that single test to determine language functionality for both C and C++.

it's further complicated by the fact that gcc-5 switched from C89 as the default standard to C11 -- C89 didn't have restrict, but C99/C11 do, so the configure tests now pass.

you could hack around it by doing:
  sed -i '/RESTRICT/s:restrict:__restrict__:' include/IL/il.h

if you wanted something more complete, then maybe use "#ifdef __cplusplus" and either do:
#ifdef __cplusplus
# undef RESTRICT_KEYWORD
#endif

or something like:
#ifdef RESTRICT_KEYWORD
# ifdef __cplusplus
#  define RESTRICT restrict
# else
#  define RESTRICT __restrict__
# endif
#endif

it also looks like RESTRICT_KEYWORD is doubly defined because the autotool logic has two independent tests:
m4/devil-definitions.m4:
AC_DEFUN([DEVIL_CHECK_RESTRICT],
AC_DEFUN([DEVIL_CHECK_RESTRICT_GNU99],

which you can see in the config.log w/gcc-5:
conftest.c:24:0: warning: "RESTRICT_KEYWORD" redefined
 #define RESTRICT_KEYWORD 1
 ^
conftest.c:23:0: note: this is the location of the previous definition
 #define RESTRICT_KEYWORD /**/
 ^

[Comment 8 Sven Eden 2015-09-03 14:24:35 UTC]

Created attachment 410928 [details, diff]
Fix usage of restrict keyword

This patch fixed the issue on my machine and devil merged fine with gcc-5.2.0

[Comment 9 Mr. Bones. (RETIRED) 2015-09-03 15:17:15 UTC]

great!  thanks for the patch.  In portage.