8347649: Build fails by clang17 after JDK-8313396

[sendaoYan]

Hi all,
This PR fix build failure by clang17 after JDK-8313396. Before this PR file src/hotspot/share/utilities/forbiddenFunctions.hpp #include <stdlib.h> and then #include "forbiddenFunctions_posix.hpp". System header file <stdlib.h> define realpath function, and file forbiddenFunctions_posix.hpp add attribute declaration for realpath function, so clang17 report compile warning "attribute declaration must precede definition". This PR switch the sequence of #include <stdlib.h> and #include "forbiddenFunctions_posix.hpp" in file src/hotspot/share/utilities/forbiddenFunctions.hpp to fix this compile warning issue.

Below code snippet shows the clang17 compile waning:

void a(const char *, char *){};
[[deprecated]] void a(const char *, char *);

clang -Wall -c ~/compiler-test/zzkk/attribute.cpp
/home/yansendao/compiler-test/zzkk/attribute.cpp:5:3: warning: attribute declaration must precede definition [-Wignored-attributes]
    5 | [[deprecated]] void a(const char *, char *);
      |   ^
/home/yansendao/compiler-test/zzkk/attribute.cpp:4:6: note: previous definition is here
    4 | void a(const char *, char *){};
      |      ^
1 warning generated.

Additional testing:

• configure and make with gcc10 with release/fastdebug debug level
• configure and make with gcc14 with release/fastdebug debug level

---

Progress

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Issue

• JDK-8347649: Build fails by clang17 after JDK-8313396 (Bug - P3)

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[bridgekeeper]

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[openjdk]

@sendaoYan The following label will be automatically applied to this pull request:

• hotspot

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[mlbridge]

Webrevs

• 00: Full (9ca37abc)

[TheShermanTanker]

I'm not sure this would work, the includes from the system are placed in front of the forbiddenFunctions includes so that the declaration from the system headers are seen first, which I think is needed for the workaround for clang. Pinging @kimbarrett for this

[kimbarrett]

I'm not sure this would work, the includes from the system are placed in front of the forbiddenFunctions includes so that the declaration from the system headers are seen first, which I think is needed for the workaround for clang. Pinging @kimbarrett for this

Yes, I've seen this PR. No, don't do this yet. I need to look into this in more detail. I already have a reason to possibly
backout JDK-8313396, because of an Oracle-internal issue. This argues I'm probably really going to have to do that.

[dholmes-ora]

The backout was done, so this PR and issue can be closed. Thanks

[sendaoYan]

Close this PR as JDK-8313396 has been backouted.