Re: [Tinycc-devel] Why is __LP64__ defined for targets for 32bits targets?

[Christian Jullien]

From a commit:

author	seyko <address@hidden>
	Sun, 15 May 2016 20:07:05 +0200 (15 21:07 +0300)
committer	seyko <address@hidden>
	Sun, 15 May 2016 20:07:05 +0200 (15 21:07 +0300)

    a patch from tcc bugzilla.
    From: Reuben Thomas
    Date: Thu, 31 Jul 2014 13:50:13 +0100
    Subject: [PATCH] libtcc.c: add memory model macros __{L,}LP64__

libtcc.c

patch | blob | blame | history

 

diff --git a/libtcc.c b/libtcc.c

index d63b86f..b0fcdf9 100644 (file)

--- a/libtcc.c

+++ b/libtcc.c

@@ -1146,9 +1146,11 @@ LIBTCCAPI TCCState *tcc_new(void)

 #if defined TCC_TARGET_PE && defined TCC_TARGET_X86_64

     tcc_define_symbol(s, "__SIZE_TYPE__", "unsigned long long");

     tcc_define_symbol(s, "__PTRDIFF_TYPE__", "long long");

+    tcc_define_symbol(s, "__LLP64__", NULL);

 #else

     tcc_define_symbol(s, "__SIZE_TYPE__", "unsigned long");

     tcc_define_symbol(s, "__PTRDIFF_TYPE__", "long");

+    tcc_define_symbol(s, "__LP64__", NULL);

 #endif

 

 

From: Tinycc-devel [mailto:address@hidden On Behalf Of Christian Jullien
Sent: dimanche 18 septembre 2016 14:06
To: address@hidden
Subject: [Tinycc-devel] Why is __LP64__ defined for targets for 32bits targets?

 

    /* TinyCC & gcc defines */

#if defined TCC_TARGET_PE && defined TCC_TARGET_X86_64

    tcc_define_symbol(s, "__SIZE_TYPE__", "unsigned long long");

    tcc_define_symbol(s, "__PTRDIFF_TYPE__", "long long");

    tcc_define_symbol(s, "__LLP64__", NULL);

#else

    tcc_define_symbol(s, "__SIZE_TYPE__", "unsigned long");

    tcc_define_symbol(s, "__PTRDIFF_TYPE__", "long");

    tcc_define_symbol(s, "__LP64__", NULL);               // <= here?

#endif

 

Compiling tcc on native 32BITS Windows for example, it defines __LP64__

This variable is specified as (see https://gcc.gnu.org/onlinedocs/gcc-4.9.2/cpp/Common-Predefined-Macros.html)

 

__LP64__

_LP64

These macros are defined, with value 1, if (and only if) the compilation is for a target where long int and pointer both use 64-bits and int uses 32-bit.

 

Testing this macro in programs compiled with tcc 32bits returns wrong behavior

 

#if defined(__LP64__)

#define MYPTR_SIZE_IN_BYTES 8

// Assume void* is a 64bits pointer which is false on Windows 32bit

#endif