openjdk-build-helper: move c compiler flags retrieval to here (from openjdk-8)

Icedtea 7 and OpenJDK 7 will need to apply new compiler flags for certain
compiler version without breaking support for older (host) compilers.

Move here so that the same code can be re-used.

Signed-off-by: André Draszik <andre.draszik@jci.com>
Signed-off-by: Richard Leitner <richard.leitner@skidata.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/classes/openjdk-build-helper.bbclass b/classes/openjdk-build-helper.bbclass
index 785ddf0..78906b0 100644
--- a/classes/openjdk-build-helper.bbclass
+++ b/classes/openjdk-build-helper.bbclass
@@ -14,3 +14,38 @@ def openjdk_build_helper_get_parallel_make(d):
         return 1
 
     return pm.partition('-j')[2].strip().split(' ')[0]
+
+# All supported cross compilers support the compiler flags that were
+# added to make compilation with gcc6 work. But the host compiler for
+# native compilation is a different story: it may be too old (for example,
+# gcc 4.9.2 on Debian Wheezy). In that case we need to check what the
+# version is and only add the flags that are appropriate for that GCC
+# version.
+def openjdk_build_helper_get_cflags_by_cc_version(d, version):
+    if version.isdigit():
+        return d.getVar('FLAGS_GCC%d' % int(version)) or ''
+    return ''
+
+def openjdk_build_helper_get_build_cflags(d):
+    def get_build_cc_version(build_cc):
+        from subprocess import Popen, PIPE
+        cmd = d.expand('%s -dumpversion' % build_cc).split()
+        cc = Popen(cmd, stdout=PIPE, stderr=PIPE)
+        return cc.communicate()[0].decode('utf-8')[0]
+
+    build_cc = d.getVar('BUILD_CC')
+    version = get_build_cc_version(build_cc)
+    return openjdk_build_helper_get_cflags_by_cc_version(d, version)
+
+def openjdk_build_helper_get_target_cflags(d):
+    import re
+
+    # in the cross case, trust that GCCVERSION is correct. This won't
+    # work if the native toolchain is Clang, but as of this writing that
+    # doesn't work anyway.
+    version = d.getVar('GCCVERSION')[0]
+    # skip non digit characters at the beginning, e.g. from "linaro-6.2%"
+    match = re.search("\d", version)
+    if match:
+        version = version[match.start():]
+    return openjdk_build_helper_get_cflags_by_cc_version(d, version)