openjdk21: fix build for clang 16 (#25879)

java/openjdk21/Portfile

@@ -2,20 +2,21 @@
 
 PortSystem          1.0
 
-name                openjdk21
+set feature 21
+name                openjdk${feature}
 # See https://openjdk-sources.osci.io/openjdk21/ for the version and build number that matches the latest '-ga' version
-version             21.0.4
+version             ${feature}.0.4
 set build 7
-revision            0
+revision            1
 categories          java devel
 supported_archs     x86_64 arm64
 license             GPL-2+
 maintainers         {breun.nl:nils @breun} openmaintainer
-description         OpenJDK 21
-long_description    JDK 21 builds of OpenJDK, the Open-Source implementation \
+description         OpenJDK ${feature} (Long Term Support)
+long_description    JDK ${feature} builds of OpenJDK, the Open-Source implementation \
                     of the Java Platform, Standard Edition, and related projects.
-homepage            https://openjdk.org/projects/jdk/21/
-master_sites        https://openjdk-sources.osci.io/openjdk21/
+homepage            https://openjdk.org/projects/jdk/${feature}/
+master_sites        https://openjdk-sources.osci.io/openjdk${feature}/
 distname            openjdk-${version}-ga
 use_xz              yes
 worksrcdir          jdk-${version}+${build}
@@ -41,6 +42,9 @@ pre-patch {
     reinplace "s|xmacosx|xwindows|g" ${worksrcpath}/make/autoconf/lib-freetype.m4
 }
 
+# Temporary workaround for clang 16: https://trac.macports.org/ticket/70819
+patchfiles          JDK-8340341-clang-16-workaround.patch
+
 set tpath ${prefix}/Library/Java
 use_xcode           yes
 use_configure    yes
@@ -146,7 +150,7 @@ test.cmd            ${bundle_dir}/Home/bin/java
 test.target         --version
 
 set jvms /Library/Java/JavaVirtualMachines
-set jdk ${jvms}/jdk-21-macports.jdk
+set jdk ${jvms}/jdk-${feature}-macports.jdk
 
 destroot {
     xinstall -m 755 -d ${destroot}${prefix}${jdk}
@@ -170,5 +174,5 @@ export JAVA_HOME=${jdk}/Contents/Home
 "
 
 livecheck.type      regex
-livecheck.url       https://openjdk-sources.osci.io/openjdk21/
-livecheck.regex     openjdk-(21\.\[0-9.\]+)-ga
+livecheck.url       ${master_sites}
+livecheck.regex     openjdk-(${feature}\.\[0-9.\]+)-ga

java/openjdk21/files/JDK-8340341-clang-16-workaround.patch

@@ -0,0 +1,14 @@
+--- make/hotspot/lib/JvmOverrideFiles.gmk.orig	2024-06-04 18:47:50
++++ make/hotspot/lib/JvmOverrideFiles.gmk	2024-09-22 23:45:41
+@@ -89,6 +89,11 @@
+     # for the clang bug was still needed.
+     BUILD_LIBJVM_loopTransform.cpp_CXXFLAGS := $(CXX_O_FLAG_NONE)
+
++    # See JDK-8340341
++    ifeq "$(firstword $(subst ., ,$(CXX_VERSION_NUMBER)))" "16"
++      BUILD_LIBJVM_stackMapTable.cpp_CXXFLAGS := "-O1"
++    endif
++
+     # The following files are compiled at various optimization
+     # levels due to optimization issues encountered at the
+     # default level. The Clang compiler issues a compile