[jdk8u-dev] RFR: 8315506: C99 compatibility issue in LinuxNativeDispatcher

[Florian Weimer]

On Fri, 1 Sep 2023 12:59:35 GMT, Andrew John Hughes <andrew at openjdk.org> wrote:

> Out of interest, what flags are you building with to make this a build failure? I've not seen that when building 8u. I don't believe this code is built with `-Werror` by default.

@gnu-andrew This was originally detected with an instrumented compilers that treats such issues errors, and logs them so that build scripts have a hard time suppressing errors (relevant to configure scripts).

Current Clang defaults `-Werror=implict-function-declaration`, so no special build flags are necessary there to trigger this issue (but I haven't tried building OpenJDK with Clang). For quite some time, expected GCC 14 to something like this as well, but I'm not sure if things will work out.

Speaking of flags, I plan to add `-Werror=implict-function-declaration -Werror=implicit-int` to the default flags in Fedora. Should I backport this change proactively to the `java-1.8.0-openjdk-portable`?

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PR Comment: https://git.openjdk.org/jdk8u-dev/pull/362#issuecomment-1702941502