Merge branch 'sverk/ct-assert'

* sverk/ct-assert:
  erts: Add compile time assert ERTS_CT_ASSERT

12 files changed, 40 insertions, 25 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index e9f5fd798b..3af7c43abf 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -5142,7 +5142,7 @@ get_map_elements_fail:
 #ifndef NO_JUMP_TABLE
 #ifdef ERTS_OPCODE_COUNTER_SUPPORT
      /* Are tables correctly generated by beam_makeops? */
-     ASSERT(sizeof(counting_opcodes) == sizeof(opcodes));
+     ERTS_CT_ASSERT(sizeof(counting_opcodes) == sizeof(opcodes));
 #ifdef DEBUG
      counting_opcodes[op_catch_end_y] = LabelAddr(lb_catch_end_y);
 #endif
diff --git a/erts/emulator/beam/erl_alloc.c b/erts/emulator/beam/erl_alloc.c
index 90cd227fae..f2bceff4eb 100644
--- a/erts/emulator/beam/erl_alloc.c
+++ b/erts/emulator/beam/erl_alloc.c
@@ -3939,7 +3939,7 @@ static Uint
 install_debug_functions(void)
 {
     int i;
-    ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
+    ERTS_CT_ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
 
     sys_memcpy((void *)real_allctrs,(void *)erts_allctrs,sizeof(erts_allctrs));
 
diff --git a/erts/emulator/beam/erl_alloc_util.c b/erts/emulator/beam/erl_alloc_util.c
index e3172dc4fb..2f277690e4 100644
--- a/erts/emulator/beam/erl_alloc_util.c
+++ b/erts/emulator/beam/erl_alloc_util.c
@@ -1442,7 +1442,7 @@ get_pref_allctr(void *extra)
 
     pref_ix = ERTS_ALC_GET_THR_IX();
 
-    ASSERT(sizeof(UWord) == sizeof(Allctr_t *));
+    ERTS_CT_ASSERT(sizeof(UWord) == sizeof(Allctr_t *));
     ASSERT(0 <= pref_ix && pref_ix < tspec->size);
 
     return tspec->allctr[pref_ix];
@@ -1861,7 +1861,7 @@ handle_delayed_dealloc(Allctr_t *allctr,
 	      * if this carrier is pulled from dc_list by cpool_fetch()
 	      */
 	    ERTS_ALC_CPOOL_ASSERT(FBLK_TO_MBC(blk) != crr);
-	    ERTS_ALC_CPOOL_ASSERT(sizeof(ErtsAllctrDDBlock_t) == sizeof(void*));
+	    ERTS_CT_ASSERT(sizeof(ErtsAllctrDDBlock_t) == sizeof(void*));
 #ifdef MBC_ABLK_OFFSET_BITS
 	    blk->u.carrier = crr;
 #else
@@ -5942,7 +5942,7 @@ erts_alcu_init(AlcUInit_t *init)
 	erts_atomic_init_nob(&sentinel->prev, (erts_aint_t) sentinel);
     }
 #endif
-    ASSERT(SBC_BLK_SZ_MASK == MBC_FBLK_SZ_MASK); /* see BLK_SZ */
+    ERTS_CT_ASSERT(SBC_BLK_SZ_MASK == MBC_FBLK_SZ_MASK); /* see BLK_SZ */
 #if HAVE_ERTS_MSEG
     ASSERT(erts_mseg_unit_size() == ERTS_SACRR_UNIT_SZ);
     max_mseg_carriers = init->mmc;
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index 5f78a7b532..d1a7ee113b 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -175,15 +175,15 @@ erts_init_gc(void)
     int i = 0, ix;
     Sint max_heap_size = 0;
 
-    ASSERT(offsetof(ProcBin,thing_word) == offsetof(struct erl_off_heap_header,thing_word));
-    ASSERT(offsetof(ProcBin,thing_word) == offsetof(ErlFunThing,thing_word));
-    ASSERT(offsetof(ProcBin,thing_word) == offsetof(ExternalThing,header));
-    ASSERT(offsetof(ProcBin,size) == offsetof(struct erl_off_heap_header,size));
-    ASSERT(offsetof(ProcBin,size) == offsetof(ErlSubBin,size));
-    ASSERT(offsetof(ProcBin,size) == offsetof(ErlHeapBin,size));
-    ASSERT(offsetof(ProcBin,next) == offsetof(struct erl_off_heap_header,next));
-    ASSERT(offsetof(ProcBin,next) == offsetof(ErlFunThing,next));
-    ASSERT(offsetof(ProcBin,next) == offsetof(ExternalThing,next));
+    ERTS_CT_ASSERT(offsetof(ProcBin,thing_word) == offsetof(struct erl_off_heap_header,thing_word));
+    ERTS_CT_ASSERT(offsetof(ProcBin,thing_word) == offsetof(ErlFunThing,thing_word));
+    ERTS_CT_ASSERT(offsetof(ProcBin,thing_word) == offsetof(ExternalThing,header));
+    ERTS_CT_ASSERT(offsetof(ProcBin,size) == offsetof(struct erl_off_heap_header,size));
+    ERTS_CT_ASSERT(offsetof(ProcBin,size) == offsetof(ErlSubBin,size));
+    ERTS_CT_ASSERT(offsetof(ProcBin,size) == offsetof(ErlHeapBin,size));
+    ERTS_CT_ASSERT(offsetof(ProcBin,next) == offsetof(struct erl_off_heap_header,next));
+    ERTS_CT_ASSERT(offsetof(ProcBin,next) == offsetof(ErlFunThing,next));
+    ERTS_CT_ASSERT(offsetof(ProcBin,next) == offsetof(ExternalThing,next));
 
     erts_test_long_gc_sleep = 0;
 
diff --git a/erts/emulator/beam/erl_instrument.c b/erts/emulator/beam/erl_instrument.c
index df7c443387..da85b86c87 100644
--- a/erts/emulator/beam/erl_instrument.c
+++ b/erts/emulator/beam/erl_instrument.c
@@ -1226,7 +1226,7 @@ erts_instr_init(int stat, int map_stat)
     mem_anchor = NULL;
 
     /* Install instrumentation functions */
-    ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
+    ERTS_CT_ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
 
     sys_memcpy((void *)real_allctrs,(void *)erts_allctrs,sizeof(erts_allctrs));
 
diff --git a/erts/emulator/beam/erl_mtrace.c b/erts/emulator/beam/erl_mtrace.c
index c8bb126687..fa1bde1c87 100644
--- a/erts/emulator/beam/erl_mtrace.c
+++ b/erts/emulator/beam/erl_mtrace.c
@@ -627,7 +627,7 @@ erts_mtrace_install_wrapper_functions(void)
     if (erts_mtrace_enabled) {
 	int i;
 	/* Install trace functions */
-	ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
+	ERTS_CT_ASSERT(sizeof(erts_allctrs) == sizeof(real_allctrs));
 
 	sys_memcpy((void *) real_allctrs,
 		   (void *) erts_allctrs,
diff --git a/erts/emulator/beam/erl_printf_term.c b/erts/emulator/beam/erl_printf_term.c
index 74e38c13df..c982dc2080 100644
--- a/erts/emulator/beam/erl_printf_term.c
+++ b/erts/emulator/beam/erl_printf_term.c
@@ -594,7 +594,7 @@ erts_printf_term(fmtfn_t fn, void* arg, ErlPfEterm term, long precision,
 		 ErlPfEterm* term_base)
 {
     int res;
-    ASSERT(sizeof(ErlPfEterm) == sizeof(Eterm));
+    ERTS_CT_ASSERT(sizeof(ErlPfEterm) == sizeof(Eterm));
 
     res = print_term(fn, arg, (Eterm)term, &precision, (Eterm*)term_base);
     if (res < 0)
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index b0276fbae0..07daabefc7 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -2318,7 +2318,6 @@ erts_active_schedulers(void)
 
     ERTS_ATOMIC_FOREACH_RUNQ(rq, as -= abs(rq->waiting));
 
-    ASSERT(as >= 0);
     return as;
 }
 
@@ -10436,7 +10435,7 @@ alloc_process(ErtsRunQueue *rq, erts_aint32_t state)
     init_arg.run_queue = rq;
     init_arg.state = state;
 
-    ASSERT(((char *) p) == ((char *) &p->common));
+    ERTS_CT_ASSERT(offsetof(Process,common) == 0);
 
     if (!erts_ptab_new_element(&erts_proc,
 			       &p->common,
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index ea5c850a30..eba07667ad 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -2225,7 +2225,7 @@ trace_gc(Process *p, Eterm what)
     Eterm* limit;
 #endif
 
-    ASSERT(sizeof(values)/sizeof(*values) == sizeof(tags)/sizeof(Eterm));
+    ERTS_CT_ASSERT(sizeof(values)/sizeof(*values) == sizeof(tags)/sizeof(Eterm));
 
     UseTmpHeap(LOCAL_HEAP_SIZE,p);
 
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 4d262ff022..d46ac9b336 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -391,7 +391,7 @@ static Port *create_port(char *name,
     /* Set default tracing */
     erts_get_default_tracing(&ERTS_TRACE_FLAGS(prt), &ERTS_TRACER_PROC(prt));
 
-    ASSERT(((char *) prt) == ((char *) &prt->common));
+    ERTS_CT_ASSERT(offsetof(Port,common) == 0);
 
 #if !ERTS_PORT_INIT_INSTR_NEED_ID
     /*
@@ -6698,7 +6698,7 @@ static void ref_to_driver_monitor(Eterm ref, ErlDrvMonitor *mon)
 {
     RefThing *refp;
     ASSERT(is_internal_ref(ref));
-    ASSERT(sizeof(RefThing) <= sizeof(ErlDrvMonitor));
+    ERTS_CT_ASSERT(sizeof(RefThing) <= sizeof(ErlDrvMonitor));
     refp = ref_thing_ptr(ref);
     memset(mon,0,sizeof(ErlDrvMonitor));
     memcpy(mon,refp,sizeof(RefThing));
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index c29d4b3777..7661bf2dc7 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -189,6 +189,22 @@ __decl_noreturn void __noreturn erl_assert_error(const char* expr, const char *f
 #endif
 
 /*
+ * Compile time assert
+ * (the actual compiler error msg can be a bit confusing)
+ */
+#if ERTS_AT_LEAST_GCC_VSN__(3,1,1)
+# define ERTS_CT_ASSERT(e) \
+    do { \
+	enum { compile_time_assert__ = __builtin_choose_expr((e),0,(void)0) }; \
+    } while(0)
+#else
+# define ERTS_CT_ASSERT(e) \
+    do { \
+        enum { compile_time_assert__ = 1/(e) }; \
+    } while (0)
+#endif
+
+/*
  * Microsoft C/C++: We certainly want to use stdarg.h and prototypes.
  * But MSC doesn't define __STDC__, unless we compile with the -Za
  * flag (strict ANSI C, no Microsoft extension).  Compiling with -Za
diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c
index db8a251fdd..c8b69b0a94 100644
--- a/erts/emulator/drivers/common/inet_drv.c
+++ b/erts/emulator/drivers/common/inet_drv.c
@@ -3948,9 +3948,9 @@ static int inet_init()
     if (0 != erl_drv_tsd_key_create("inet_buffer_stack_key", &buffer_stack_key))
 	goto error;
 
-    ASSERT(sizeof(struct in_addr) == 4);
+    ERTS_CT_ASSERT(sizeof(struct in_addr) == 4);
 #   if defined(HAVE_IN6) && defined(AF_INET6)
-    ASSERT(sizeof(struct in6_addr) == 16);
+    ERTS_CT_ASSERT(sizeof(struct in6_addr) == 16);
 #   endif
 
     INIT_ATOM(ok);
@@ -3996,7 +3996,7 @@ static int inet_init()
 #ifdef HAVE_SCTP
     /* Check the size of SCTP AssocID -- currently both this driver and the
        Erlang part require 32 bit: */
-    ASSERT(sizeof(sctp_assoc_t)==ASSOC_ID_LEN);
+    ERTS_CT_ASSERT(sizeof(sctp_assoc_t)==ASSOC_ID_LEN);
 #   if defined(HAVE_SCTP_BINDX)
     p_sctp_bindx = sctp_bindx;
 #     if defined(HAVE_SCTP_PEELOFF)