Enable mono cross-build on SunOS-like OS (#19932)

Summary:
* wire `$(Compiler)` in `mono.proj`, that comes from `eng/build.sh`.
* add configurations for illumos cross-compilation.
* set `-Werror=strict-prototypes` for `madvise` and `posix_madvise` introspection, which is used during the compilation.
* implement `mono-threads-sunos.c`.
* add some solaris-specific thread priority levels.

With this set of changes, `dotnet hwapp.dll` works with mono flavored `System.Private.CoreLib.dll` and `libcoreclr.so` on SmartOS 2020.

Contributes to: dotnet/runtime#34944.

Co-authored-by: am11 <am11@users.noreply.github.com>

1 files changed, 25 insertions, 9 deletions

diff --git a/configure.ac b/configure.ac
index c6cfaf2f55c..8e983863377 100644
--- a/configure.ac
+++ b/configure.ac
@@ -139,6 +139,7 @@ platform_ios=no
 host_darwin=no
 host_linux=no
 build_darwin=no
+host_sunos=no
 
 case "$host" in
 	wasm32*)
@@ -397,13 +398,14 @@ case "$host" in
 		use_sigposix=yes
 		;;
 	*-*-solaris*)
-		CPPFLAGS="$CPPFLAGS -DGC_SOLARIS_THREADS -DGC_SOLARIS_PTHREADS -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -DUSE_MMAP -DUSE_MUNMAP -DHOST_SOLARIS"
+		CPPFLAGS="$CPPFLAGS -DGC_SOLARIS_THREADS -DGC_SOLARIS_PTHREADS -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -DUSE_MMAP -DUSE_MUNMAP -DHOST_SOLARIS -D__EXTENSIONS__ -D_XPG4_2"
 		need_link_unlink=yes
 		libmono_cflags="-D_REENTRANT"
 		libgc_threads=pthreads
 		has_dtrace=yes
 		use_sigposix=yes
 		enable_solaris_tar_check=yes
+		host_sunos=yes
 		;;
 	*-*-darwin*)
 		parallel_mark="Disabled_Currently_Hangs_On_MacOSX"
@@ -2274,14 +2276,13 @@ if test x$host_win32 = xno; then
 	AC_CHECK_FUNCS(getresuid)
 	AC_CHECK_FUNCS(setresuid)
 	AC_CHECK_FUNCS(kqueue)
-	# IBM provides a compatibility library for i offering this function.
+	# IBM provides a compatibility library for offering this function.
 	# BSDs and others, have execinfo in base or packages.
 	AC_SEARCH_LIBS(backtrace_symbols, execinfo util)
 	# Two-step so it sets it in config.h
 	AC_CHECK_FUNCS(backtrace_symbols)
 	AC_CHECK_FUNCS(mkstemp)
 	AC_CHECK_FUNCS(mmap)
-	AC_CHECK_FUNCS(madvise)
 	AC_CHECK_FUNCS(getrusage)
 	AC_CHECK_FUNCS(getpriority)
 	AC_CHECK_FUNCS(setpriority)
@@ -2747,7 +2748,7 @@ if test x$host_win32 = xno; then
 	dnl *** Checks for libxnet    ***
 	dnl *****************************
 	case "${host}" in
-		*solaris* )
+		*solaris*)
 			AC_MSG_CHECKING(for Solaris XPG4 support)
 			if test -f /usr/lib/libxnet.so; then
 				CPPFLAGS="$CPPFLAGS -D_XOPEN_SOURCE=500"
@@ -3215,7 +3216,6 @@ if test x$host_win32 = xno; then
 	AC_CHECK_FUNCS(remap_file_pages)
 	AC_CHECK_FUNCS(posix_fadvise)
 	AC_CHECK_FUNCS(posix_fallocate)
-	AC_CHECK_FUNCS(posix_madvise)
 	AC_CHECK_FUNCS(vsnprintf)
 	AC_CHECK_FUNCS(sendfile)
 	AC_CHECK_FUNCS(gethostid sethostid)
@@ -3921,6 +3921,19 @@ if test x$host_win32 = xno; then
 
 	AC_CHECK_DECL(IN_EXCL_UNLINK, [AC_DEFINE(HAVE_IN_EXCL_UNLINK, 1, [IN_EXCL_UNLINK])], [], [[#include <sys/inotify.h>]])
 
+	if test x$host_sunos = xyes; then
+		# set -Werror=strict-prototypes, to match the flags used during the compilation.
+		ORIG_CFLAGS="$CFLAGS"
+		CFLAGS="$CFLAGS -Werror=strict-prototypes"
+	fi
+
+	AC_CHECK_FUNCS(madvise)
+	AC_CHECK_FUNCS(posix_madvise)
+
+	if test x$host_sunos = xyes; then
+		CFLAGS="$ORIG_CFLAGS"
+	fi
+
 	# *** End of Mono.Native checks ***
 else
 	AM_CONDITIONAL(ENABLE_GSS, false)
@@ -6836,9 +6849,9 @@ if test x$with_core = xonly; then
 				ICU_CFLAGS="$CPPFLAGS -DPALEXPORT="" -DOSX_ICU_LIBRARY_PATH=AS_ESCAPE(\"/usr/lib/libicucore.dylib\", '\"') -DTARGET_UNIX -DU_DISABLE_RENAMING -Wno-reserved-id-macro -Wno-documentation -Wno-documentation-unknown-command -Wno-switch-enum -Wno-covered-switch-default -Wno-covered-switch-default -Wno-extra-semi-stmt -Wno-unknown-warning-option -Wno-deprecated-declarations"
 			fi
 			CPPFLAGS=$ORIG_CPPFLAGS
-		elif test x$platform_android = xyes; then 
+		elif test x$platform_android = xyes; then
 			ICU_CFLAGS="-DPALEXPORT="" -DHAVE_UDAT_STANDALONE_SHORTER_WEEKDAYS -DHAVE_SET_MAX_VARIABLE -DTARGET_UNIX -DTARGET_ANDROID -Wno-reserved-id-macro -Wno-documentation -Wno-documentation-unknown-command -Wno-switch-enum -Wno-covered-switch-default -Wno-covered-switch-default -Wno-extra-semi-stmt -Wno-unknown-warning-option"
-			have_sys_icu=yes 
+			have_sys_icu=yes
 		elif test x$host_linux = xyes; then
 			AC_CHECK_LIB(icuuc, main, LIBS=$LIBS,
 				[AC_MSG_ERROR([Cannot find libicuuc, try installing libicu-dev (or the appropriate package for your platform).])])
@@ -6848,14 +6861,17 @@ if test x$with_core = xonly; then
 			if test x$have_sys_icu = xyes; then
 				ICU_CFLAGS="-DPALEXPORT="" -DTARGET_UNIX -Wno-reserved-id-macro -Wno-documentation -Wno-documentation-unknown-command -Wno-switch-enum -Wno-covered-switch-default -Wno-covered-switch-default -Wno-extra-semi-stmt -Wno-unknown-warning-option"
 			fi
+		elif test x$host_sunos = xyes; then
+			ICU_CFLAGS="-DPALEXPORT="" -DTARGET_UNIX -Wno-reserved-id-macro -Wno-documentation -Wno-documentation-unknown-command -Wno-switch-enum -Wno-covered-switch-default -Wno-extra-semi-stmt -Wno-unknown-warning-option"
+			have_sys_icu=yes
 		else
 			GLOBALIZATION_SHIM_DEFINES="-DNO_GLOBALIZATION_SHIM"
 		fi
 		AC_SUBST(ICU_CFLAGS)
-	else 
+	else
 		GLOBALIZATION_SHIM_DEFINES="-DNO_GLOBALIZATION_SHIM"
 	fi
-else 
+else
 	GLOBALIZATION_SHIM_DEFINES="-DNO_GLOBALIZATION_SHIM"
 fi