[configure] Add failsafe for missing submodules (mono/mono#13957)

GitHub provides a way to download a .zip/.tar.gz of the repository content in their UI, however the archive doesn't contain git submodules.

The mono build then fails with confusing "missing file" errors.

Since GitHub doesn't let us disable the archive download we should at least add some logic to detect this broken case and bail out.

Commit migrated from https://github.com/mono/mono/commit/e8caaa1dbd880767bcf07ccfa8b9f695377ddd8d

diff --git a/src/mono/Makefile.am b/src/mono/Makefile.am
index 78d1f62..06dab03 100644 (file)
--- a/src/mono/Makefile.am
+++ b/src/mono/Makefile.am
@@ -25,9 +25,8 @@ DIST_SUBDIRS = $(build_with_msvc) m4 mk po $(libgc_dir) llvm mono ikvm-native su
 
 all: update_submodules
 
-SUBMODULE_ERROR='Could not recursively update all git submodules. You may experience compilation problems if some submodules are out of date'
 update_submodules:
-       @$(srcdir)/scripts/update_submodules.sh
+       @cd $(srcdir) && scripts/update_submodules.sh
 
 .PHONY: update_submodules