Use gnu for ruby build because strptime is provided by posix (#5660)

* Use gnu for ruby build because strptime is provided by posix

* Move option to extconf.rb

* Remove unused code in Rakefile

* Add config files for kokoro test

* Use gnu 11

* Define _XOPEN_SOURCE

* Add gnu11 option

* Remove XOPEN

* Try base_cc_flags

* Try config_options

* Move time.h to top

* Try -D_XOPEN_SOURCE=700

* Define XOPEN_SOURCE directly

* Try extconf.rb

* Try CFLAGS

* Try ext.cross_config_options

* Make mac ruby release job fail on error

* Try again

* Try define _XOPEN_SOURCE in extconf.rb

* Try again

* Define __USE_XOPEN

* Remove 2.6.0

* No mingw

* Throw error on mingw

* Remove XOPEN_SOURCE in upb

* Add back mingw

* Remove comment

kokoro/release/python/linux/continuous.cfg

+# Config file for running tests in Kokoro
+build_file: "protobuf/kokoro/release/python/linux/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/python/linux/presubmit.cfg

+# Config file for running tests in Kokoro
+build_file: "protobuf/kokoro/release/python/linux/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/python/macos/continuous.cfg

+# Configuration for Mac OSX release builds
+build_file: "protobuf/kokoro/release/python/macos/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/python/macos/presubmit.cfg

+# Configuration for Mac OSX release builds
+build_file: "protobuf/kokoro/release/python/macos/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/ruby/linux/continuous.cfg

+# Configuration for Linux release builds
+build_file: "protobuf/kokoro/release/ruby/linux/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/ruby/linux/presubmit.cfg

+# Configuration for Linux release builds
+build_file: "protobuf/kokoro/release/ruby/linux/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/ruby/linux/ruby/ruby_build.sh

 #!/bin/bash
 
+set -ex
+
 # Build protoc
 if test ! -e src/protoc; then
   ./autogen.sh

kokoro/release/ruby/macos/continuous.cfg

+# Configuration for Mac OSX release builds
+build_file: "protobuf/kokoro/release/ruby/macos/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/ruby/macos/presubmit.cfg

+# Configuration for Mac OSX release builds
+build_file: "protobuf/kokoro/release/ruby/macos/build_artifacts.sh"
+
+action {
+  define_artifacts {
+    regex: "github/protobuf/artifacts/**"
+  }
+}

kokoro/release/ruby/macos/ruby/ruby_build.sh

 #!/bin/bash
 
+set -ex
+
 # Build protoc
 if test ! -e src/protoc; then
   ./autogen.sh

ruby/ext/google/protobuf_c/extconf.rb

@@ -2,7 +2,13 @@
 
 require 'mkmf'
 
-$CFLAGS += " -std=c99 -O3 -DNDEBUG"
+if RUBY_PLATFORM =~ /darwin/ || RUBY_PLATFORM =~ /linux/
+  # XOPEN_SOURCE needed for strptime:
+  # https://stackoverflow.com/questions/35234152/strptime-giving-implicit-declaration-and-undefined-reference
+  $CFLAGS += " -std=c99 -O3 -DNDEBUG -D_XOPEN_SOURCE=700"
+else
+  $CFLAGS += " -std=c99 -O3 -DNDEBUG"
+end
 
 
 if RUBY_PLATFORM =~ /linux/

ruby/ext/google/protobuf_c/upb.c

@@ -12610,11 +12610,6 @@ done:
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-
-/* Need to define __USE_XOPEN before including time.h to make strptime work. */
-#ifndef __USE_XOPEN
-#define __USE_XOPEN
-#endif
 #include <time.h>
 
 
@@ -14127,12 +14122,19 @@ static bool end_timestamp_base(upb_json_parser *p, const char *ptr) {
   memcpy(timestamp_buf + UPB_TIMESTAMP_BASE_SIZE, "GMT", 3);
   timestamp_buf[UPB_TIMESTAMP_BASE_SIZE + 3] = 0;
 
+#if defined __MINGW32__ || defined __MINGW64__
+  upb_status_seterrf(
+      &p->status, "error parsing timestamp: mingw doesn't support strptime");
+  upb_env_reporterror(p->env, &p->status);
+  return false;
+#else
   /* Parse seconds */
   if (strptime(timestamp_buf, "%FT%H:%M:%S%Z", &p->tm) == NULL) {
     upb_status_seterrf(&p->status, "error parsing timestamp: %s", buf);
     upb_env_reporterror(p->env, &p->status);
     return false;
   }
+#endif
 
   /* Clean up buffer */
   multipart_end(p);