gdb: add configure option to disable compile

GDB's compile subsystem is deeply tied to GDB's ability to understand
DWARF. A future patch will add the option to disable DWARF at configure
time, but for that to work, the compile subsystem will need to be
entirely disabled as well, so this patch adds that possibility.

I also think there is motive for a security conscious user to disable
compile for it's own sake. Considering that the code is quite
unmaintained, and depends on an equally unmaintained gcc plugin, there
is a case to be made that this is an unnecessary increase in the attack
surface if a user knows they won't use the subsystem. Additionally, this
can make compilation slightly faster and the final binary is around 3Mb
smaller. But these are all secondary to the main goal of being able to
disable dwarf at configure time.

To be able to achieve optional compilation, some of the code that
interfaces with compile had to be changed. All parts that directly
called compile things have been wrapped by ifdefs checking for compile
support.  The file compile/compile.c has been setup in a similar way to
how python's and guile's main file has been setup, still being compiled
but only for with placeholder command.

Finally, to avoid several new errors, a new TCL proc was introduced to
gdb.exp, allow_compile_tests, which checks if the "compile" command is
recognized before the inferior is started and otherwise skips the compile
tests. All tests in the gdb.compile subfolder have been updated to use
that, and the test gdb.base/filename-completion also uses this. The proc
skip_compile_feature_tests to recognize when the subsystem has been
disabled at compile time.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>

19 files changed, 50 insertions, 5 deletions

diff --git a/gdb/testsuite/gdb.base/filename-completion.exp b/gdb/testsuite/gdb.base/filename-completion.exp
index 03ead59..a1dd974 100644
--- a/gdb/testsuite/gdb.base/filename-completion.exp
+++ b/gdb/testsuite/gdb.base/filename-completion.exp
@@ -381,11 +381,15 @@ proc run_mid_line_completion_tests { root cmd } {
 proc run_quoting_and_escaping_tests { root } {
     # Test all the commands which allow quoting of filenames, and
     # which require whitespace to be escaped in unquoted filenames.
-    foreach_with_prefix cmd { file exec-file symbol-file add-symbol-file \
-				  remove-symbol-file \
-				  "target core" "target exec" "target tfile" \
-				  "maint print c-tdesc" "compile file" \
-				  "save gdb-index" "save gdb-index -dwarf-5" } {
+    set all_cmds { file exec-file symbol-file add-symbol-file \
+		      remove-symbol-file \
+		      "target core" "target exec" "target tfile" \
+		      "maint print c-tdesc" "save gdb-index"
+		      "save gdb-index -dwarf-5" }
+    if { [allow_compile_tests] } {
+	lappend all_cmds "compile file"
+    }
+    foreach_with_prefix cmd $all_cmds {
 	# Try each test placing the filename as the first argument
 	# then again with a quoted string immediately after the
 	# command.  This works because the filename completer will
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-anonymous.exp b/gdb/testsuite/gdb.compile/compile-cplus-anonymous.exp
index 3e76d38..ddad628 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-anonymous.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-anonymous.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-array-decay.exp b/gdb/testsuite/gdb.compile/compile-cplus-array-decay.exp
index 505a4e1..c7d15ce 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-array-decay.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-array-decay.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++ additional_flags=-std=c++11}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-inherit.exp b/gdb/testsuite/gdb.compile/compile-cplus-inherit.exp
index 1a5f60a..9ef1e83 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-inherit.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-inherit.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-member.exp b/gdb/testsuite/gdb.compile/compile-cplus-member.exp
index 5ffbb30..ac9111c 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-member.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-member.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-method.exp b/gdb/testsuite/gdb.compile/compile-cplus-method.exp
index 0a0e0fa..bcbfbb0 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-method.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-method.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-namespace.exp b/gdb/testsuite/gdb.compile/compile-cplus-namespace.exp
index 3ab8ece..2abc366 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-namespace.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-namespace.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-nested.exp b/gdb/testsuite/gdb.compile/compile-cplus-nested.exp
index 19efd4f..247d270 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-nested.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-nested.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-print.exp b/gdb/testsuite/gdb.compile/compile-cplus-print.exp
index 594f94a..e4413f0 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-print.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-print.exp
@@ -19,6 +19,8 @@ standard_testfile
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 set options {}
 if [test_compiler_info gcc*] {
     lappend options additional_flags=-g3
diff --git a/gdb/testsuite/gdb.compile/compile-cplus-virtual.exp b/gdb/testsuite/gdb.compile/compile-cplus-virtual.exp
index 8761df5..a770208 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus-virtual.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus-virtual.exp
@@ -23,6 +23,8 @@ require allow_cplus_tests
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[prepare_for_testing $testfile $testfile $srcfile \
 	 {debug nowarnings c++}]} {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile-cplus.exp b/gdb/testsuite/gdb.compile/compile-cplus.exp
index 711f299..35ae692 100644
--- a/gdb/testsuite/gdb.compile/compile-cplus.exp
+++ b/gdb/testsuite/gdb.compile/compile-cplus.exp
@@ -19,6 +19,8 @@ standard_testfile .c compile-shlib.c compile-constvar.S compile-nodebug.c
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 set options {}
 if { [test_compiler_info gcc*] || [test_compiler_info clang*] } {
     lappend options additional_flags=-g3
diff --git a/gdb/testsuite/gdb.compile/compile-ifunc.exp b/gdb/testsuite/gdb.compile/compile-ifunc.exp
index b004bd7..e490890 100644
--- a/gdb/testsuite/gdb.compile/compile-ifunc.exp
+++ b/gdb/testsuite/gdb.compile/compile-ifunc.exp
@@ -17,6 +17,8 @@ load_lib compile-support.exp
 
 require allow_ifunc_tests
 
+require allow_compile_tests
+
 standard_testfile
 
 require is_c_compiler_gcc
diff --git a/gdb/testsuite/gdb.compile/compile-ops.exp b/gdb/testsuite/gdb.compile/compile-ops.exp
index f75e02c..cfbe2b0 100644
--- a/gdb/testsuite/gdb.compile/compile-ops.exp
+++ b/gdb/testsuite/gdb.compile/compile-ops.exp
@@ -22,6 +22,8 @@ load_lib dwarf.exp
 # This test can only be run on targets which support DWARF-2 and use gas.
 require dwarf2_support
 
+require allow_compile_tests
+
 require is_c_compiler_gcc
 
 standard_testfile .c -dbg.S
diff --git a/gdb/testsuite/gdb.compile/compile-print.exp b/gdb/testsuite/gdb.compile/compile-print.exp
index f8f2297..61ce750 100644
--- a/gdb/testsuite/gdb.compile/compile-print.exp
+++ b/gdb/testsuite/gdb.compile/compile-print.exp
@@ -19,6 +19,8 @@ standard_testfile
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if { [prepare_for_testing "failed to prepare" "$testfile"] } {
     return -1
 }
diff --git a/gdb/testsuite/gdb.compile/compile-setjmp.exp b/gdb/testsuite/gdb.compile/compile-setjmp.exp
index f387a05..ad8732b 100644
--- a/gdb/testsuite/gdb.compile/compile-setjmp.exp
+++ b/gdb/testsuite/gdb.compile/compile-setjmp.exp
@@ -19,6 +19,8 @@ standard_testfile .c compile-setjmp-mod.c
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if { [prepare_for_testing "failed to prepare" $testfile] } {
     return -1
 }
diff --git a/gdb/testsuite/gdb.compile/compile-tls.exp b/gdb/testsuite/gdb.compile/compile-tls.exp
index 2f8dc5a..45e290e 100644
--- a/gdb/testsuite/gdb.compile/compile-tls.exp
+++ b/gdb/testsuite/gdb.compile/compile-tls.exp
@@ -19,6 +19,8 @@ standard_testfile .c
 
 require is_c_compiler_gcc
 
+require allow_compile_tests
+
 if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
 	 executable {debug}] != "" } {
     return -1
diff --git a/gdb/testsuite/gdb.compile/compile.exp b/gdb/testsuite/gdb.compile/compile.exp
index 2c2e321..5128dc62 100644
--- a/gdb/testsuite/gdb.compile/compile.exp
+++ b/gdb/testsuite/gdb.compile/compile.exp
@@ -15,6 +15,8 @@
 
 load_lib compile-support.exp
 
+require allow_compile_tests
+
 standard_testfile .c compile-shlib.c compile-constvar.S compile-nodebug.c
 
 require is_c_compiler_gcc
diff --git a/gdb/testsuite/lib/compile-support.exp b/gdb/testsuite/lib/compile-support.exp
index aa8aaf3..6d7a4ce 100644
--- a/gdb/testsuite/lib/compile-support.exp
+++ b/gdb/testsuite/lib/compile-support.exp
@@ -45,6 +45,9 @@ proc _do_check_compile {expr} {
 	    # This appears to be a bug in the compiler plugin.
 	    set result "apparent compiler plugin bug"
 	}
+	-re "This command is not supported." {
+	    set result "compiler disabled at configure time"
+	}
 	-re "\r\n$gdb_prompt $" {
 	}
     }
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 3349da7..8486ff0 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -2799,6 +2799,12 @@ gdb_caching_proc allow_python_tests {} {
     return [expr {[string first "--with-python" $output] != -1}]
 }
 
+# Return a 1 if GDB was configured to support compile commands.
+gdb_caching_proc allow_compile_tests {} {
+    set output [remote_exec host $::GDB "$::INTERNAL_GDBFLAGS -ex \"compile int x = 1\" -batch"]
+    return [expr {[string first "The program must be running" $output] != -1}]
+}
+
 # Return a 1 for configurations that use system readline rather than the
 # in-repo copy.