8241476: Linux build warnings issued on gcc 9

[tsayao]

Simple fix to remove annoying warnings.

---

Progress

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Issue

• JDK-8241476: Linux build warnings issued on gcc 9

Reviewers

• Kevin Rushforth (kcr - Reviewer)
• Ambarish Rapte (arapte - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jfx pull/150/head:pull/150
$ git checkout pull/150

[bridgekeeper]

👋 Welcome back tsayao! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request.

[mlbridge]

Webrevs

• 03: Full - Incremental (92f1b9a)
• 02: Full - Incremental (67adeae)
• 01: Full - Incremental (3164ab3)
• 00: Full (6e185d8)

[kevinrushforth]

The problem is that gcc, for whatever reason, started issuing a (useless) warning if you pass the -Werror=implicit-function-declaration option to gcc for C++ files. I don't like the solution of removing that flag for C files. I think the better solution will be to have a set of options that are common to both C and C++ (all but this one currently), and then add -Werror=implicit-function-declaration only to the options for C. Until then, I think we live with this warning. It's better than losing the checking for C files.

[tsayao]

Like this?

I think all C builds are covered. Gstreamer seems to have a Makefile with the flags. Not sure about libxml and libxlst inside javafx.web.

[johanvos]

I think it's better to split the flags between CFLAGS and CPPFLAGS (as is done in OpenJDK). The -Werror=implicit-function-declaration is extremely useful for C files, and we don't want to risk that this somehow got lost.
If we use CFLAGS and CPPFLAGS, we can pass the latter as CXXFLAGS to cmake, so that should be fairly easy.

[kevinrushforth]

I took a look yesterday and came to the same conclusion that what we really want are separate C and C++ flags. For now, the only difference would be the presence or absence of -Werror=implicit-function-declaration, but it would allow for other differences in the future if needed.

[kevinrushforth]

/reviewers 2

[openjdk]

@kevinrushforth
The number of required reviews for this PR is now set to 2 (with at least 1 of role reviewers).

[tsayao]

Please, let me know if this is the desired way to do it. If not, I will rework it. Thanks.

[kevinrushforth]

This is roughly what I had in mind. I want to test it, and also take a look at the WebKit and media builds as well. WebKit uses the flags from linux.gradle, and is mostly C++, so I think it needs no changes. Media does not use any flags from linux.gradle -- only the jfxmedia project has C++ files on Linux. I guess it should be fine, too, but I'll see.

[kevinrushforth]

The build changes in linux.gradle look good. I tested it, and all warnings are gone (including those in WebKit) except for the ones in the jfxmedia sub-project of javafx.media.

Two comments:

1. I changed the bug title in JBS to refer to gcc 9 rather than Ubuntu to reflect the actual cause of the additional warnings. Can you update the title of this PR to match?

8241476: Linux build warnings issued on gcc 9

2. Can you add the following change to your PR as well? This will fix the remaining warnings in jfxmedia:

--- a/modules/javafx.media/src/main/native/jfxmedia/projects/linux/Makefile
+++ b/modules/javafx.media/src/main/native/jfxmedia/projects/linux/Makefile
@@ -41,7 +41,6 @@ ifdef HOST_COMPILE
                   -Wextra \
                   -Wformat-security \
                   -fstack-protector \
-                  -Werror=implicit-function-declaration \
                   -Werror=trampolines \
                  -msse2 \
                  -DGSTREAMER_LITE

[tsayao]

Done.

[kevinrushforth]

Looks good.

[kevinrushforth]

@johanvos or @arapte Can one of you be the second reviewer on this?

[arapte]

After this change below c files would be compiled without -Werror=implicit-function-declaration option.
modules/javafx.media/src/main/native/jfxmedia/Utils/ColorConverter.c

modules/javafx.graphics/src/main/native-glass/gtk/wrapped.c
modules/javafx.graphics/src/main/native-glass/gtk/launcher.c

This can be addressed in follow on issue. Recording the files here for track.
Looks good to me.

[openjdk]

@tsayao This change now passes all automated pre-integration checks. When the change also fulfills all project specific requirements, type /integrate in a new comment to proceed. After integration, the commit message will be:

8241476: Linux build warnings issued on gcc 9

Reviewed-by: kcr, arapte

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Since the source branch of this PR was last updated there have been 32 commits pushed to the master branch. Since there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid automatic rebasing, please merge master into your branch, and then specify the current head hash when integrating, like this: /integrate 9d50c4cc01856c0c6a07fa27e4258216c2f2d0e8.

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[tsayao]

/integrate

[openjdk]

@tsayao
Your change (at version 92f1b9a) is now ready to be sponsored by a Committer.

[kevinrushforth]

/sponsor

[openjdk]

@kevinrushforth @tsayao The following commits have been pushed to master since your change was applied:

• 9d50c4c: Merge
• 4d69a0d: 8241629: [macos10.15] Long startup delay playing media over https on Catalina
• b1fdc45: 8242209: Increase web native thread stack size for x86 mode
• e1cb191: 8240694: [macos 10.15] JavaFX Media hangs on some video files on Catalina
• c154538: 8242106: [macos] Remove obsolete GlassView2D.m class
• 3f663e3: 8240262: iOS refresh rate is capped to 30 Hz
• 231879a: 8241710: NullPointerException while entering empty submenu with "arrow right"
• 470c7d0: 8230809: HTMLEditor formatting lost when selecting all (CTRL-A)
• fda015c: 8242167: ios keyboard handling
• 844460b: 8242163: Android keyboard integration fails
• 364c64a: 8241249: NPE in TabPaneSkin.perfromDrag
• 418675a: 8236840: Memory leak when switching ButtonSkin
• 247a65d: 8236971: [macos] Gestures handled incorrectly due to missing events
• 560ef17: 8241455: Memory leak on replacing selection/focusModel
• ef37669: Merge
• 5906521: 8241370: Crash in JPEGImageLoader after fix for JDK-8212034
• 159f651: 8240542: Switch FX build to use JDK 14 as boot JDK
• 6d098fe: 8234959: FXMLLoader does not populate ENGINE_SCOPE Bindings with FILENAME and ARGV
• d7f13f4: 8089828: RTL Orientation, the flag of a mnemonic is not placed under the mnemonic letter.
• 9ecc107: 8240539: Upgrade gradle to version 6.3
• f3a3ea0: 8234471: Canvas in webview displayed with wrong scale on Windows
• f2bca9f: Merge
• 6900d29: Merge
• e91bec4: Merge
• 66a8f49: Merge
• fde42da: Merge
• e21fd1f: Merge
• 443c845: Merge
• 31e63de: Merge
• 14c6938: 8236798: Enhance FX scripting support
• bfb2d0e: Merge
• 39f6127: Merge

Your commit was automatically rebased without conflicts.

Pushed as commit 7044cef.