Make support for global constructors and global destructors be

configurable, so people who do not need or want ctor/dtor support
can disable it and make their binaries a little bit smaller.
 -Erik

6 files changed, 68 insertions, 11 deletions

diff --git a/libc/Makefile b/libc/Makefile
index 595f69e4a..4a5110f0e 100644
--- a/libc/Makefile
+++ b/libc/Makefile
@@ -30,6 +30,12 @@
 TOPDIR=../
 include $(TOPDIR)Rules.mak
 
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+CRTOBJS="../../lib/crti.o ../../lib/crt0.o ../../lib/crtn.o"
+else
+CRTOBJS="../../lib/crt0.o"
+endif
+
 DIRS = misc pwd_grp stdio string termios inet signal stdlib sysdeps unistd
 
 # Check if the target architecture has a version script for
@@ -49,7 +55,8 @@ shared: $(TOPDIR)lib/$(LIBNAME)
 	@rm -rf tmp
 	@mkdir tmp
 	$(AR) rv ./tmp/libgcc-need.a
-	@(cd tmp && CC=$(CC) LD=$(LD) LDFLAGS=$(CPU_LDFLAGS-y) NM=$(NM) AR=$(AR) LIBGCC=$(LIBGCC) \
+	@(cd tmp && CC=$(CC) LD=$(LD) LDFLAGS=$(CPU_LDFLAGS-y) NM=$(NM) AR=$(AR) \
+		LIBGCC=$(LIBGCC) CRTOBJS=$(CRTOBJS) \
 		/bin/sh $(TOPDIR)../extra/scripts/get-needed-libgcc-objects.sh)
 	$(LD) $(LDFLAGS) $(VERSION_SCRIPT) -soname=$(SHARED_MAJORNAME) -o $(SHARED_FULLNAME) \
 		--whole-archive ./tmp/libgcc-need.a $(LIBNAME) --no-whole-archive \
diff --git a/libc/sysdeps/linux/arm/crt0.S b/libc/sysdeps/linux/arm/crt0.S
index ad4865cc1..a930ff3f2 100644
--- a/libc/sysdeps/linux/arm/crt0.S
+++ b/libc/sysdeps/linux/arm/crt0.S
@@ -80,6 +80,7 @@ _start:
 	ldr r2,[sp, #8]
 #endif
 
+#ifdef __UCLIBC_CTOR_DTOR__
 	/* Store the address of _init in r3 as an argument to main() */
 	ldr r3, =_init
 
@@ -89,6 +90,9 @@ _start:
 
 	/* Ok, now run uClibc's main() -- shouldn't return */
 	bl	__uClibc_start_main
+#else
+	bl	__uClibc_main
+#endif
 
 	/* Crash if somehow `exit' returns anyways.  */
 	bl abort
diff --git a/libc/sysdeps/linux/common/Makefile b/libc/sysdeps/linux/common/Makefile
index f66c09f31..8e0ed9485 100644
--- a/libc/sysdeps/linux/common/Makefile
+++ b/libc/sysdeps/linux/common/Makefile
@@ -24,11 +24,6 @@
 TOPDIR=../../../../
 include $(TOPDIR)Rules.mak
 
-SAFECFLAGS=$(WARNINGS) $(CPU_CFLAGS-y) $(OPTIMIZATION) -fno-builtin
-ifeq ($(strip $(DOPIC)),y)
-SAFECFLAGS+=-fPIC
-endif
-
 CSRC=	waitpid.c getdnnm.c gethstnm.c getcwd.c \
 	mkfifo.c setegid.c wait.c getpagesize.c seteuid.c \
 	wait3.c setpgrp.c getdtablesize.c create_module.c ptrace.c \
@@ -44,13 +39,21 @@ COBJS=$(patsubst %.c,%.o, $(CSRC))
 MSRC=syscalls.c
 MOBJ=$(shell ./list_syscalls.sh)
 
+ifeq ($(strip $(UCLIBC_CTOR_DTOR)),y)
+CTOR_TARGETS=$(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o
+SAFECFLAGS=$(WARNINGS) $(CPU_CFLAGS-y) $(OPTIMIZATION) -fno-builtin
+ifeq ($(strip $(DOPIC)),y)
+SAFECFLAGS+=-fPIC
+endif
+endif
+
 OBJ=$(COBJS) $(MOBJ)
 
 all: $(STR_SYSCALLS) $(OBJ) $(LIBC)
 
 $(LIBC): ar-target
 
-ar-target: $(OBJ) $(TOPDIR)lib/crti.o $(TOPDIR)lib/crtn.o
+ar-target: $(OBJ) $(CTOR_TARGETS)
 	$(AR) $(ARFLAGS) $(LIBC) $(OBJ)
 	(cd $(TOPDIR)lib/; ln -fs crt0.o crt1.o)
 
diff --git a/libc/sysdeps/linux/i386/crt0.S b/libc/sysdeps/linux/i386/crt0.S
index 97f1fde63..be66b9a2d 100644
--- a/libc/sysdeps/linux/i386/crt0.S
+++ b/libc/sysdeps/linux/i386/crt0.S
@@ -61,6 +61,7 @@ _start:
 	pushl %ebp      /* callers %ebp (frame pointer) */
 	movl %esp,%ebp  /* mark callers stack frame as invalid */
 
+#ifdef __UCLIBC_CTOR_DTOR__
 	/* Push .init and .fini arguments to __uClibc_start_main() on the stack */
 	pushl $_fini
 	pushl $_init
@@ -72,6 +73,14 @@ _start:
 
 	/* Ok, now run uClibc's main() -- shouldn't return */
 	call __uClibc_start_main
+#else
+	/* Push envp, argc, and argc arguments to __uClibc_start_main() on the stack */ 
+	pushl %eax	/* Environment pointer */
+	pushl %ebx	/* Argument pointer */
+	pushl %ecx	/* And the argument count */
+
+	call __uClibc_main
+#endif
 
 	/* Crash if somehow `exit' returns anyways.  */
 	hlt
diff --git a/libc/sysdeps/linux/mips/crt0.S b/libc/sysdeps/linux/mips/crt0.S
index fd1f4b9d4..052229819 100644
--- a/libc/sysdeps/linux/mips/crt0.S
+++ b/libc/sysdeps/linux/mips/crt0.S
@@ -30,6 +30,7 @@ __start:
 	addu a2, a0, 1	    /* argv[0] program name (ordinal->cardinal) */
         sll  a2, a2, 2	    /* multiple by 4 */
 	add  a2, a2, a1	    /* a2 now points to start of envp */
+#ifdef __UCLIBC_CTOR_DTOR__
 	la   a3, _init	    /* a3 is address of _init */
 	addiu sp, sp, -24   /* 16 + 4 rounded up to multiple of 8 */
 			    /* multiple of 8 for longlong/double support */
@@ -38,6 +39,9 @@ __start:
 	
 	/* Ok, now run uClibc's main() -- shouldn't return */
 	jal  __uClibc_start_main
+#else
+	jal  __uClibc_main
+#endif
 
 	addiu sp, sp, 24    /* undo stack argument */
 
diff --git a/libc/sysdeps/linux/sh/crt0.S b/libc/sysdeps/linux/sh/crt0.S
index e74ae86c4..a27775ed0 100644
--- a/libc/sysdeps/linux/sh/crt0.S
+++ b/libc/sysdeps/linux/sh/crt0.S
@@ -48,6 +48,34 @@ _start:
 	mov.l @r15+,r4
 	mov r15, r5
 
+#if ! defined __UCLIBC_CTOR_DTOR__
+	/*
+	 * Setup the value for the environment pointer:
+	 * r6 = (argc + 1) * 4
+	 * r6 += argv (in delay slot)
+	 */
+	mov r4,r6
+	add #1,r6
+	shll2 r6
+	add r5, r6
+
+	/* jump to __uClibc_main (argc, argv, envp) */
+	mov.l L_main, r0
+	jsr @r0
+	nop /* delay slot */
+
+	/* We should not get here. */
+	mov.l L_abort, r0
+	jmp @r0
+	nop
+
+_start_end:	
+	.align	2
+
+L_main:
+	.long   __uClibc_main /* in libuClibc.*.so */
+
+#else /* __UCLIBC_CTOR_DTOR__ */
 	/* Push the finip argument to __uClibc_start_main() onto the stack */
 	mov.l L_fini,r6
 	mov.l r6,@-r15
@@ -72,10 +100,12 @@ _start:
 	mov.l L_abort, r0
 	jmp @r0
 	nop
-
 _start_end:	
 	.align	2
 
+L_main:
+	.long   __uClibc_start_main /* in libuClibc.*.so */
+
 	.weak   _init
 	.type   _init,@function
 _init:
@@ -87,13 +117,13 @@ _init:
 	.weak   _fini
 	.set    _fini,_init
 
-L_main:
-	.long   __uClibc_start_main /* in libuClibc.*.so */
-
 L_init:
       .long   _init
 L_fini:
       .long   _fini
+
+#endif
+
 L_abort: 
       .long   abort