Hello Yasumasa,
I prefer to avoid such pragma usage, as for me code is more readable
without it.
So we can add array-bounds to DISABLED_WARNINGS_gcc in
make/lib/Awt2dLibraries.gmk for BUILD_LIBJAVAJPEG and BUILD_LIBMLIB_IMAGE.
We can nullify row_pointers and image_data after setjmp call to remove
warnings in splashscreen_png.c:
diff -r 729dffc8afa0
src/java.desktop/share/native/libsplashscreen/splashscreen_png.c
--- a/src/java.desktop/share/native/libsplashscreen/splashscreen_png.c
+++ b/src/java.desktop/share/native/libsplashscreen/splashscreen_png.c
@@ -77,6 +77,8 @@ SplashDecodePng(Splash * splash, png_rw_
#else
if (setjmp(png_jmpbuf(png_ptr))) {
#endif
+ row_pointers = NULL;
+ image_data = NULL;
goto done;
}
(or declare them as volatile, but I prefer the first option).
BTW, there is another issue about this splashscreen_png.c gcc build
failure [1].
[1] https://bugs.openjdk.java.net/browse/JDK-8080695
Thanks,
Alexander.
On 05/28/2015 06:27 AM, Yasumasa Suenaga wrote:
I've uploaded webrev:
http://cr.openjdk.java.net/~ysuenaga/JDK-8081295/webrev.01/
Please review.
Thanks,
Yasumasa
On 2015/05/28 12:19, Yasumasa Suenaga wrote:
Hi all,
I tried to build jdk9/dev on Fedora22 with GCC 5.1.1, however, it was failed.
I found several problems:
System:
Fedora release 22 (Twenty Two) x86_64
- gcc-5.1.1-1.fc22.x86_64
Problems:
1. Array bounds check in GCC
- jdk/src/java.desktop/share/native/libjavajpeg/jcmaster.c
- jdk/src/java.desktop/share/native/libjavajpeg/jquant1.c
- jdk/src/java.desktop/share/native/libmlib_image/mlib_ImageLookUp_64.c
- jdk/src/java.desktop/share/native/libmlib_image/mlib_c_ImageLookUp_f.c
It seems to be bug of GCC:
Bug 59124: [4.8/4.9/5/6 Regression] Wrong warnings "array subscript is
above array bounds"
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59124
I think implementations of these files have no problem.
So I propose to ignore warning(s) of compiler through pragma option as
workaround when we use GCC [1].
2. Local variables might be clobbered
- jdk/src/java.desktop/share/native/libsplashscreen/splashscreen_png.c
SplashDecodePng() calls setjmp(3).
Some local variables initialize before setjmp() call, and use after it.
Their initial values are only used at cleanup code (*done* label) and
actual values are stored only after setjmp() call.
So I think we can ignore this error through pragma option [1].
3. Incorrect condition
- jdk/src/jdk.jdwp.agent/share/native/libjdwp/eventFilter.c
searchAllSourceNames() returns int value. However, branch condition in
eventFilterRestricted_passesFilter() treats it as boolean value.
I received a comment from Erik to use --disable-warnings-as-errors,
however I could not avoid error in 3.
Thanks,
Yasumasa
[1] https://gcc.gnu.org/onlinedocs/gcc/Diagnostic-Pragmas.html
