Fix internal error from command line with unbalanced --start-lib/--end-lib.

The problem is that while the command line isn't trivially empty,
it contains no input files. As gold tries to configure the number
of threads to use based on the number of input files, this causes
the assertion failure above. Fix this problem by making the logic
in gold.cc more robust and also adding a better error message
about --start-lib to options.cc.

gold/
	PR gold/22406
	* gold.cc (queue_initial_tasks) Check for number of real input files.
	* options.cc (Command_line::process) Check for unterminated --start-lib
	options.
	* testsuite/Makefile.am: Add new test script.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/check_empty_command_lines.sh: New test script.

1 files changed, 17 insertions, 10 deletions

diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index c42c472..9bb3b56 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -74,7 +74,20 @@ check_PROGRAMS = $(am__EXEEXT_1) $(am__EXEEXT_2) $(am__EXEEXT_3) \
 @NATIVE_OR_CROSS_LINKER_TRUE@am__append_1 = object_unittest \
 @NATIVE_OR_CROSS_LINKER_TRUE@	binary_unittest leb128_unittest \
 @NATIVE_OR_CROSS_LINKER_TRUE@	overflow_unittest
-@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_2 = incremental_test.sh \
+
+# ---------------------------------------------------------------------
+# These tests test the output of gold (end-to-end tests).  In
+# particular, they make sure that gold can link "difficult" object
+# files, and the resulting object files run correctly.  These can only
+# run if we've built ld-new for the native architecture (that is,
+# we're not cross-compiling it), since we run ld-new as part of these
+# tests.  We use the gcc-specific flag '-B' to use our linker instead
+# of the default linker, which is why we only run our tests under gcc.
+
+# Test empty command line error conditions.
+@GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_2 =  \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	empty_command_line_test.sh \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	incremental_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_comdat_test.sh gc_tls_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	gc_orphan_section_test.sh \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	pr14265.sh pr20717.sh \
@@ -5137,6 +5150,8 @@ check-html recheck-html:
 	rv=0; $(MAKE) $(AM_MAKEFLAGS) $$target || rv=$$?; \
 	$(MAKE) $(AM_MAKEFLAGS) $(TEST_SUITE_HTML) TEST_LOGS= || exit 4; \
 	exit $$rv
+empty_command_line_test.sh.log: empty_command_line_test.sh
+	@p='empty_command_line_test.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 incremental_test.sh.log: incremental_test.sh
 	@p='incremental_test.sh'; $(am__check_pre) $(LOG_COMPILE) "$$tst" $(am__check_post)
 gc_comdat_test.sh.log: gc_comdat_test.sh
@@ -5906,15 +5921,7 @@ uninstall-am:
 @GCC_TRUE@@NATIVE_OR_CROSS_LINKER_TRUE@	(cd gcctestdir && $(LN_S) $(abs_top_builddir)/../gas/as-new as)
 @NATIVE_OR_CROSS_LINKER_TRUE@overflow_unittest.o: overflow_unittest.cc
 @NATIVE_OR_CROSS_LINKER_TRUE@	$(CXXCOMPILE) -O3 -c -o $@ $<
-
-# ---------------------------------------------------------------------
-# These tests test the output of gold (end-to-end tests).  In
-# particular, they make sure that gold can link "difficult" object
-# files, and the resulting object files run correctly.  These can only
-# run if we've built ld-new for the native architecture (that is,
-# we're not cross-compiling it), since we run ld-new as part of these
-# tests.  We use the gcc-specific flag '-B' to use our linker instead
-# of the default linker, which is why we only run our tests under gcc.
+@GCC_TRUE@@NATIVE_LINKER_TRUE@empty_command_line_test.sh: gcctestdir/ld
 
 # Each of these .o's is a useful, small complete program.  They're
 # particularly useful for making sure ld-new's flags do what they're