Bug 716295 part 6 - Create elfhack tests for both DT_INIT and DT_INIT_ARRAY. r=nfroyd

build/unix/elfhack/Makefile.in

@@ -38,7 +38,8 @@ endif
 CSRCS := \
   inject/$(CPU).c \
   inject/$(CPU)-noinit.c \
-  test.c \
+  test-ctors.c \
+  test-array.c \
   $(NULL)
 
 ifndef CROSS_COMPILE
@@ -53,33 +54,39 @@ OS_CXXFLAGS := $(filter-out -pedantic,$(OS_CXXFLAGS))
 
 include $(topsrcdir)/config/rules.mk
 
-test$(DLL_SUFFIX): test.$(OBJ_SUFFIX) elfhack $(CSRCS:.c=.$(OBJ_SUFFIX))
-	$(MKSHLIB) $(LDFLAGS) $<
+test-array$(DLL_SUFFIX) test-ctors$(DLL_SUFFIX): %$(DLL_SUFFIX): %.$(OBJ_SUFFIX) elfhack $(filter inject/%,$(CSRCS:.c=.$(OBJ_SUFFIX)))
+	$(MKSHLIB) $(LDFLAGS) $< -nostartfiles
 	@echo ===
 	@echo === If you get failures below, please file a bug describing the error
 	@echo === and your environment \(compiler and linker versions\), and use
 	@echo === --disable-elf-hack until this is fixed.
 	@echo ===
+	# Fail if the library doesn't have $(DT_TYPE) .dynamic info
+	$(TOOLCHAIN_PREFIX)readelf -d $@ | grep '($(DT_TYPE))'
 	@rm -f $@.bak
 	$(CURDIR)/elfhack -b -f $@
 	# Fail if the backup file doesn't exist
 	[ -f "$@.bak" ]
 	# Fail if the new library doesn't contain less relocations
-	[ $$(objdump -R $@.bak | wc -l) -gt $$(objdump -R $@ | wc -l) ]
+	[ $$($(TOOLCHAIN_PREFIX)objdump -R $@.bak | wc -l) -gt $$(objdump -R $@ | wc -l) ]
 
-.PRECIOUS: test$(DLL_SUFFIX)
+test-array$(DLL_SUFFIX): DT_TYPE=INIT_ARRAY
+test-ctors$(DLL_SUFFIX): DT_TYPE=INIT
 
-GARBAGE += test$(DLL_SUFFIX) test$(DLL_SUFFIX).bak
+.PRECIOUS: test-array$(DLL_SUFFIX) test-ctors$(DLL_SUFFIX)
 
-libs:: test$(DLL_SUFFIX)
+GARBAGE += test-array$(DLL_SUFFIX) test-ctors$(DLL_SUFFIX) test-array$(DLL_SUFFIX).bak test-ctors$(DLL_SUFFIX).bak
+
+libs:: test-array$(DLL_SUFFIX) test-ctors$(DLL_SUFFIX)
 
 ifndef CROSS_COMPILE
-dummy: dummy.$(OBJ_SUFFIX) test$(DLL_SUFFIX)
+dummy: dummy.$(OBJ_SUFFIX)
 	$(CC) -o $@ $^ $(LDFLAGS)
 
 libs:: dummy
 	# Will either crash or return exit code 1 if elfhack is broken
-	LD_LIBRARY_PATH=$(CURDIR) $(CURDIR)/dummy
+	LD_PRELOAD=$(CURDIR)/test-array$(DLL_SUFFIX) $(CURDIR)/dummy
+	LD_PRELOAD=$(CURDIR)/test-ctors$(DLL_SUFFIX) $(CURDIR)/dummy
 
 GARBAGE += dummy
 endif

build/unix/elfhack/dummy.c

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-extern __attribute__((visibility("default"))) int print_status();
+extern __attribute__((visibility("default"), weak)) int print_status();
 
 int main() {
     return print_status();

build/unix/elfhack/test-array.c

@@ -0,0 +1,8 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "test.c"
+
+__attribute__((section(".init_array"), used))
+static void (*init_array[])() = { end_test, test };

build/unix/elfhack/test-ctors.c

@@ -0,0 +1,17 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "test.c"
+
+/* Recent binutils would put .ctors content into a .init_array section */
+__attribute__((section(".manual_ctors"), used))
+static void (*ctors[])() = { (void (*)())-1, end_test, test, NULL };
+
+__attribute__((section(".init")))
+void _init() {
+    void (**func)() = &ctors[sizeof(ctors) / sizeof(void (*)()) - 1];
+    while (*(--func) != (void (*)())-1) {
+        (*func)();
+    }
+}

build/unix/elfhack/test.c

@@ -125,14 +125,14 @@ int print_status() {
  * following sections as part of the PT_TLS segment. */
 __thread int foo[1024];
 
-__attribute__((constructor)) void end_test() {
+void end_test() {
     static int count = 0;
     /* Only exit when both constructors have been called */
     if (++count == 2)
         ret = 0;
 }
 
-__attribute__((constructor)) void test() {
+void test() {
     int i = 0, j = 0;
 #define DEF_(a,i,w) \
     if (a[i++] != str_ ## w) return;