Re: [Gm2] Potential woe with gm2-4.1.2

[john o goyo]

On 8 Oct 2013, at 10:32, Gaius Mulley wrote:
[...]
> for example on my system I get the following:
>
> $ cat chello.mod
> MODULE chello ;
>
> FROM libc IMPORT printf ;
>
> BEGIN
>   printf("hello world\n")
> END chello.
[...]

One main module works as it should.  (in particular, your example  
works.)

Witness (with a few blank lines added for clarity):

johng: 541 [init]=> cat main.mod
MODULE main;

FROM other IMPORT n;

BEGIN
  n := 1;
  HALT
END main.

johng: 542 [init]=> cat other.def
DEFINITION MODULE other;

VAR
  n :CARDINAL;

END other.

johng: 543 [init]=> cat other.mod
IMPLEMENTATION MODULE other;

BEGIN
  n := 1
END other.

johng: 544 [init]=> gm2 -g -c main.mod
johng: 545 [init]=> nm main.o

main.o:

[Index]   Value          Size        Type  Bind  Other Shndx   Name

[--- chopped --]
[18]    |             0|           0|NOTY |GLOB |0    |UNDEF  | 
M2RTS_HALT
[20]    |            56|          12|FUNC |GLOB |0    |1      | 
_M2_main_finish
[15]    |             0|          56|FUNC |GLOB |0    |1      | 
_M2_main_init
[19]    |             0|           0|NOTY |GLOB |0    |UNDEF  | 
__gxx_personality_v0
[1]     |             0|           0|FILE |LOCL |0    |ABS    |main.mod
[17]    |             0|           0|NOTY |GLOB |0    |UNDEF  |other_n

johng: 546 [init]=> gm2 -g -c other.mod
johng: 547 [init]=> nm other.o

other.o:

[Index]   Value          Size        Type  Bind  Other Shndx   Name

[-- chopped --]
[18]    |            36|          12|FUNC |GLOB |0    |1      | 
_M2_other_finish
[14]    |             0|          36|FUNC |GLOB |0    |1      | 
_M2_other_init
[17]    |             0|           0|NOTY |GLOB |0    |UNDEF  | 
__gxx_personality_v0
[1]     |             0|           0|FILE |LOCL |0    |ABS    |other.mod
[16]    |             0|           4|OBJT |GLOB |0    |4      |other_n

johng: 548 [init]=> gm2 -g main.mod other.mod
johng: 549 [init]=> ./a.out
johng: 550 [init]=> nm a.out |grep _init
[823]   |    4295007808|          12|FUNC |GLOB |0    |12     | 
_M2_ASCII_init
[758]   |    4295085788|          12|FUNC |GLOB |0    |166    | 
_M2_Debug_init
[553]   |    4295047496|          20|FUNC |GLOB |0    |97     | 
_M2_FIO_init
[709]   |    4295007832|          20|FUNC |GLOB |0    |14     | 
_M2_IO_init
[611]   |    4295097296|          12|FUNC |GLOB |0    |249    | 
_M2_Indexing_init
[827]   |    4295090416|          76|FUNC |GLOB |0    |194    | 
_M2_M2EXCEPTION_init
[659]   |    4295012200|          92|FUNC |GLOB |0    |29     | 
_M2_M2RTS_init
[812]   |    4295017452|          12|FUNC |GLOB |0    |62     | 
_M2_NumberIO_init
[748]   |    4295090824|          20|FUNC |GLOB |0    |198    | 
_M2_RTExceptions_init
[549]   |    4295038592|          12|FUNC |GLOB |0    |87     | 
_M2_SYSTEM_init
[631]   |    4295088360|         100|FUNC |GLOB |0    |184    | 
_M2_StdIO_init
[693]   |    4295088140|          12|FUNC |GLOB |0    |178    | 
_M2_Storage_init
[724]   |    4295075256|          32|FUNC |GLOB |0    |148    | 
_M2_StrIO_init
[786]   |    4295078520|          12|FUNC |GLOB |0    |156    | 
_M2_StrLib_init
[647]   |    4294991672|           8|FUNC |GLOB |0    |9      | 
_M2_SysExceptions_init
[540]   |    4295087540|          12|FUNC |GLOB |0    |171    | 
_M2_SysStorage_init
[681]   |    4294985396|           8|FUNC |GLOB |0    |9      | 
_M2_errno_init
[592]   |    4294985328|          36|FUNC |GLOB |0    |9      | 
_M2_other_init
[608]   |    4294991252|           8|FUNC |GLOB |0    |9      | 
_M2_termios_init
[595]   |    4295007760|          28|FUNC |GLOB |0    |10     |_init
[485]   |    4294999472|         640|FUNC |LOCL |0    |9      | 
uw_init_context_1

johng: 551 [init]=> grep main_init main_m2.cpp
extern "C" void _M2_main_init (int argc, char *argv[]);
       _M2_main_init (argc, argv);

johng: 552 [init]=> gcc -g -c main_m2.cpp
johng: 553 [init]=> gm2 -g main_m2.o main.o other.o
johng: 554 [init]=> ./a.out
Abort (core dumped)

So, oddly enough, the function call is in the C++ file in the object  
file but seems to be absent or mangled in the link-editted version.   
Compiling the C++ and linking it direclty works.

This is truly odd (and I appreciate probably very difficult for you to  
investigate).

john