The same hotspot sources and makefile deliver into our JDK6 releases, and formal builds of JDK6 are done on some very old Linux systems, RH2.1?, which I think is before 2000.
-kto On Apr 29, 2011, at 4:34 PM, Omair Majid wrote: > On 04/29/2011 07:13 PM, David Katleman wrote: >> Hi Omair! >> >> On 4/29/2011 3:59 PM, Omair Majid wrote: >>> Hi, >>> >>> http://cr.openjdk.java.net/~omajid/webrevs/gcc-46-support/ >>> >>> The patch adds support for building hotspot with gcc 4.6. gcc 4.6 >>> changed how arguments are handled. It now treats -export-dynamic as it >>> treats any other -efoo option: it thinks xport-dynamic is the entry >>> point and passes this information to the linker. Since -export-dynamic >>> is not passed to the linker, not all symbols will be exported by the >>> linker. The bfd-based linker, given the invalid entry point >>> xport-dynamic, simply ignores it. The gold linker, however, crashes >>> causing the build to fail. >>> >>> Since -export-dynamic is a linker option, the correct way to pass it >>> is using -Wl,-export-dynamic (or -Xlinker -export-dynamic). We have >>> had this patch in IcedTea6 for a while now, but it would be nice if >>> this was in OpenJDK too. >> >> Seems like your change should be surrounded by an ifneq that enables >> your change for 4.6 and later >> > > While I could certainly do that, I dont understand why it's needed. The patch > keeps things backwards compatible. With the patch applied, I can still build > hotspot with older versions of gcc/binutils. > > -export-dynamic is a linker option and has been for a (long) while now. I am > actually not sure what the earliest version of ld that supports > export-dynamic is, but -Wl,-export-dynamic is mentioned on > http://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html which was > last updated 2003. Surely all versions of gcc/ld that we now use must support > this? > > If you still think this needs to be conditional (although I strongly disagree > that it needs to be), I can post another webrev. > >> Example elsewhere in the file >> >>> 129 # Except for a few acceptable ones >>> 130 # Since GCC 4.3, -Wconversion has changed its meanings to warn >>> these implicit >>> 131 # conversions which might affect the values. To avoid that, we >>> need to turn >>> 132 # it off explicitly. >>> 133 ifneq "$(shell expr \( $(CC_VER_MAJOR) \> 4 \) \| \( \( >>> $(CC_VER_MAJOR) = 4 \) \& \( $(CC_VER_MINOR) \>= 3 \) \))" "0" >>> 134 ACCEPTABLE_WARNINGS = -Wpointer-arith -Wsign-compare >>> 135 else >>> 136 ACCEPTABLE_WARNINGS = -Wpointer-arith -Wconversion -Wsign-compare >>> 137 endif >> > > Thanks for the example. I will keep this in mind whenever a gcc change needs > to be conditional. > > Cheers, > Omair
