Allow disabling symbol versioning at configure time

Due to missing symbol versioning support in uClibc calls to versioned
functions that internally call different version of themselves results
in infinite recursion.

Introduce macro SYMBOL_VERSIONING and use it instead of plain SHARED to
decide whether symbol versioning is needed. Control this macro
definition with new configure option --disable-symbol-versioning.

Signed-off-by: Max Filippov <[email protected]>
Signed-off-by: Mark Wielaard <[email protected]>

10 files changed, 42 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 9a0a82db..d45bf673 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2015-04-23  Max Filippov  <[email protected]>
+
+	* configure.ac: Add --disable-symbol-versioning.
+
 2015-04-14  Mark Wielaard  <[email protected]>
 
 	* configure.ac (ac_cv_c99): Add explicit checks for all GNU99
diff --git a/config/ChangeLog b/config/ChangeLog
index 586ebb03..bff3b6dd 100644
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,7 @@
+2015-04-23  Max Filippov  <[email protected]>
+
+	* eu.am (DEFS.os): New variable.
+
 2015-03-18  Petr Machata  <[email protected]>
 
 	* known-dwarf.awk (comment): Drop all uses of this variable.
diff --git a/config/eu.am b/config/eu.am
index faf8add4..6103a3ef 100644
--- a/config/eu.am
+++ b/config/eu.am
@@ -38,16 +38,22 @@ AM_CFLAGS = -std=gnu99 -Wall -Wshadow -Wformat=2 \
 
 COMPILE.os = $(filter-out -fprofile-arcs -ftest-coverage, $(COMPILE))
 
+DEFS.os = -DPIC -DSHARED
+if SYMBOL_VERSIONING
+DEFS.os += -DSYMBOL_VERSIONING
+else
+endif
+
 %.os: %.c %.o
 if AMDEP
-	if $(COMPILE.os) -c -o $@ -fpic -DPIC -DSHARED -MT $@ -MD -MP \
+	if $(COMPILE.os) -c -o $@ -fpic $(DEFS.os) -MT $@ -MD -MP \
 	  -MF "$(DEPDIR)/$*.Tpo" `test -f '$<' || echo '$(srcdir)/'`$<; \
 	then cat "$(DEPDIR)/$*.Tpo" >> "$(DEPDIR)/$*.Po"; \
 	     rm -f "$(DEPDIR)/$*.Tpo"; \
 	else rm -f "$(DEPDIR)/$*.Tpo"; exit 1; \
 	fi
 else
-	$(COMPILE.os) -c -o $@ -fpic -DPIC -DSHARED $<
+	$(COMPILE.os) -c -o $@ -fpic $(DEFS.os) $<
 endif
 
 CLEANFILES = *.gcno *.gcda
diff --git a/configure.ac b/configure.ac
index ed2c9644..be015734 100644
--- a/configure.ac
+++ b/configure.ac
@@ -241,6 +241,13 @@ AS_HELP_STRING([--disable-textrelcheck],
                [Disable textrelcheck being a fatal error]))
 AM_CONDITIONAL(FATAL_TEXTREL, [test "x$enable_textrelcheck" != "xno"])
 
+AC_ARG_ENABLE([symbol-versioning],
+AS_HELP_STRING([--disable-symbol-versioning],
+               [Disable symbol versioning in shared objects]))
+AM_CONDITIONAL(SYMBOL_VERSIONING, [test "x$enable_symbol_versioning" != "xno"])
+AS_IF([test "x$enable_symbol_versioning" = "xno"],
+      [AC_MSG_WARN([Disabling symbol versioning breaks ABI compatibility.])])
+
 dnl The directories with content.
 
 dnl Documentation.
diff --git a/lib/ChangeLog b/lib/ChangeLog
index 44152131..166f047d 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,7 @@
+2015-04-23  Max Filippov  <[email protected]>
+
+	* eu-config.h: Use SYMBOL_VERSIONING as guard.
+
 2014-01-17  Lei Zhang  <[email protected]>
 
 	* crc32_file.c: Include config.h.
diff --git a/lib/eu-config.h b/lib/eu-config.h
index 3afff26a..5bb21c14 100644
--- a/lib/eu-config.h
+++ b/lib/eu-config.h
@@ -163,7 +163,7 @@ asm (".section predict_data, \"aw\"; .previous\n"
 #define ELFUTILS_HEADER(name) <lib##name.h>
 
 
-#ifdef SHARED
+#ifdef SYMBOL_VERSIONING
 # define OLD_VERSION(name, version) \
   asm (".globl _compat." #version "." #name "\n" \
        "_compat." #version "." #name " = " #name "\n" \
@@ -181,8 +181,8 @@ asm (".section predict_data, \"aw\"; .previous\n"
 # define OLD_VERSION(name, version) /* Nothing for static linking.  */
 # define NEW_VERSION(name, version) /* Nothing for static linking.  */
 # define COMPAT_VERSION_NEWPROTO(name, version, prefix) \
-  error "should use #ifdef SHARED"
-# define COMPAT_VERSION(name, version, prefix) error "should use #ifdef SHARED"
+  error "should use #ifdef SYMBOL_VERSIONING"
+# define COMPAT_VERSION(name, version, prefix) error "should use #ifdef SYMBOL_VERSIONING"
 #endif
 
 
diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index d4cd3f5a..cbaad852 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,12 @@
+2015-04-23  Max Filippov  <[email protected]>
+
+	* core-file.c (_compat_without_executable_dwfl_core_file_report):
+	Guard with SYMBOL_VERSIONING.
+	* dwfl_module_build_id.c (_compat_vaddr_at_end_dwfl_module_build_id):
+	Likewise.
+	* dwfl_report_elf.c (_compat_without_add_p_vaddr_dwfl_report_elf):
+	Likewise.
+
 2015-04-02  Mark Wielaard  <[email protected]>
 
 	* segment.c (insert): Check correct number of lookup_elts.
diff --git a/libdwfl/core-file.c b/libdwfl/core-file.c
index 324e9d2d..bbe0899d 100644
--- a/libdwfl/core-file.c
+++ b/libdwfl/core-file.c
@@ -588,7 +588,7 @@ dwfl_core_file_report (Dwfl *dwfl, Elf *elf, const char *executable)
 INTDEF (dwfl_core_file_report)
 NEW_VERSION (dwfl_core_file_report, ELFUTILS_0.158)
 
-#ifdef SHARED
+#ifdef SYMBOL_VERSIONING
 int _compat_without_executable_dwfl_core_file_report (Dwfl *dwfl, Elf *elf);
 COMPAT_VERSION_NEWPROTO (dwfl_core_file_report, ELFUTILS_0.146,
 			 without_executable)
diff --git a/libdwfl/dwfl_module_build_id.c b/libdwfl/dwfl_module_build_id.c
index 350bbf83..c9a42ca7 100644
--- a/libdwfl/dwfl_module_build_id.c
+++ b/libdwfl/dwfl_module_build_id.c
@@ -101,7 +101,7 @@ dwfl_module_build_id (Dwfl_Module *mod,
 INTDEF (dwfl_module_build_id)
 NEW_VERSION (dwfl_module_build_id, ELFUTILS_0.138)
 
-#ifdef SHARED
+#ifdef SYMBOL_VERSIONING
 COMPAT_VERSION (dwfl_module_build_id, ELFUTILS_0.130, vaddr_at_end)
 
 int
diff --git a/libdwfl/dwfl_report_elf.c b/libdwfl/dwfl_report_elf.c
index 3a4ae2ef..624284cf 100644
--- a/libdwfl/dwfl_report_elf.c
+++ b/libdwfl/dwfl_report_elf.c
@@ -321,7 +321,7 @@ dwfl_report_elf (Dwfl *dwfl, const char *name, const char *file_name, int fd,
 INTDEF (dwfl_report_elf)
 NEW_VERSION (dwfl_report_elf, ELFUTILS_0.156)
 
-#ifdef SHARED
+#ifdef SYMBOL_VERSIONING
 Dwfl_Module *
   _compat_without_add_p_vaddr_dwfl_report_elf (Dwfl *dwfl, const char *name,
 					       const char *file_name, int fd,