JDK-8259949: x86 32-bit build fails when -fcf-protection is passed in the compiler flags

[gnu-andrew]

The latest GCC fails if -fcf-protection is used with an x86 (32-bit) target that doesn't support CMOV:

https://gcc.gnu.org/git/?p=gcc.git;a=blobdiff;f=gcc/config/i386/i386-options.c;h=a70f6edf7b0bfa6994db372c2507dbacb5526646;hp=6819a04238965f0ad63b10323823caa2fb8b147c;hb=77d372abec0fbf2cfe922e3140ee3410248f979e;hpb=5ebdd53534db25401473db5f6a0ad30f41410241

At least back to OpenJDK 11, the JDK build forces -march=i586 and the build fails with '-fcf-protection is not compatible with this target'

This patch uses -march=i686 instead if -fcf-protection is detected in the compiler flags. It also makes it clear which is being set in the configure output, rather than silently setting the flag.

---

Progress

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Issue

• JDK-8259949: x86 32-bit build fails when -fcf-protection is passed in the compiler flags

Reviewers

• Erik Joelsson (@erikj79 - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/2153/head:pull/2153
$ git checkout pull/2153

[bridgekeeper]

👋 Welcome back andrew! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

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[mlbridge]

Webrevs

• 00: Full (bb20cdd)

[openjdk]

@gnu-andrew This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8259949: x86 32-bit build fails when -fcf-protection is passed in the compiler flags

Use -march=i686 instead of -march=i586 if -fcf-protection is passed to the build as CMOV is required

Reviewed-by: erikj

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 8 new commits pushed to the master branch:

• 5891509: 8259947: (fs) Optimize UnixPath.encode implementation
• 69f90b5: 8259843: initialize dli_fname array before calling dll_address_to_library_name
• 52ed2aa: 8259786: initialize last parameter of getpwuid_r
• 70b5b31: 8257664: HTMLEditorKit: Wrong CSS relative font sizes
• 0b01d69: 8260005: Shenandoah: Remove unused AlwaysTrueClosure in ShenandoahConcurrentRootScanner::roots_do()
• 0529480: 8259867: Move encoding checks into ZipCoder
• 7c32ffe: 8258383: vmTestbase/gc/g1/unloading/tests/unloading_compilation_level[1,2,3] time out without TieredCompilation
• 9f21bb6: 8259983: do not use uninitialized expand_ms value in G1CollectedHeap::expand_heap_after_young_collection

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[gnu-andrew]

/summary Use -march=i686 instead of -march=i586 if -fcf-protection is passed to the build as CMOV is required

[openjdk]

@gnu-andrew Setting summary to Use -march=i686 instead of -march=i586 if -fcf-protection is passed to the build as CMOV is required

[gnu-andrew]

/integrate

[openjdk]

@gnu-andrew Since your change was applied there have been 8 commits pushed to the master branch:

• 5891509: 8259947: (fs) Optimize UnixPath.encode implementation
• 69f90b5: 8259843: initialize dli_fname array before calling dll_address_to_library_name
• 52ed2aa: 8259786: initialize last parameter of getpwuid_r
• 70b5b31: 8257664: HTMLEditorKit: Wrong CSS relative font sizes
• 0b01d69: 8260005: Shenandoah: Remove unused AlwaysTrueClosure in ShenandoahConcurrentRootScanner::roots_do()
• 0529480: 8259867: Move encoding checks into ZipCoder
• 7c32ffe: 8258383: vmTestbase/gc/g1/unloading/tests/unloading_compilation_level[1,2,3] time out without TieredCompilation
• 9f21bb6: 8259983: do not use uninitialized expand_ms value in G1CollectedHeap::expand_heap_after_young_collection

Your commit was automatically rebased without conflicts.

Pushed as commit 0785147.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[gnu-andrew]

/backport jdk13u-dev

[openjdk]

@gnu-andrew Unknown command backport - for a list of valid commands use /help.

[gnu-andrew]

/help

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