On Thu, 23 Jan 2025 13:48:06 GMT, Joachim Kern <jk...@openjdk.org> wrote:
>> We (SAP) try to introduce the ‘IBM Open XL C/C++ for AIX 17.1.2’ (based on >> clang 17) as a feasible compiler for jdk25, because in combination with the >> 17.1.3 runtime this would enable the support for ubsan. >> Unfortunately, the new compiler comes along with a new set of compiler >> warnings turned into errors by -Werror. >> One of the warnings is -Wtentative-definitions. It is fired when a variable >> definition in a header is found: >> /jdk/src/java.desktop/share/native/libawt/awt/image/imageInitIDs.h:36:20: >> error: possible missing 'extern' on global variable definition in header >> [-Werror,-Wtentative-definitions] >> 36 | IMGEXTERN jfieldID g_BImgRasterID; >> | ^ >> From now on headers allow only extern declarations of variables. The >> definition must take place in a c/cpp file. This means e.g. >> imageInitIDs.h:36:20 >> 36 extern jfieldID g_BImgRasterID; >> and the corresponding c-File >> jfieldID g_BImgRasterID; >> >> The other possible solution would be to compile everything with >> -Wno-tentative-definitions >> which could be set in flags-cflags.m4, if compiling with clang 17. > > Joachim Kern has updated the pull request incrementally with one additional > commit since the last revision: > > remove old solution ------------- Marked as reviewed by ihse (Reviewer). PR Review: https://git.openjdk.org/jdk/pull/23236#pullrequestreview-2570094539
