Return to asm-underscore.m4 CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / libiconv / srcm4

Annotation of embedaddon/libiconv/srcm4/asm-underscore.m4, revision 1.1.1.1

1.1       misho       1: # asm-underscore.m4 serial 1
                      2: dnl Copyright (C) 2010-2011 Free Software Foundation, Inc.
                      3: dnl This file is free software; the Free Software Foundation
                      4: dnl gives unlimited permission to copy and/or distribute it,
                      5: dnl with or without modifications, as long as this notice is preserved.
                      6: 
                      7: dnl From Bruno Haible. Based on as-underscore.m4 in GNU clisp.
                      8: 
                      9: # gl_ASM_SYMBOL_PREFIX
                     10: # Tests for the prefix of C symbols at the assembly language level and the
                     11: # linker level. This prefix is either an underscore or empty. Defines the
                     12: # C macro USER_LABEL_PREFIX to this prefix, and sets ASM_SYMBOL_PREFIX to
                     13: # a stringified variant of this prefix.
                     14: 
                     15: AC_DEFUN([gl_ASM_SYMBOL_PREFIX],
                     16: [
                     17:   dnl We don't use GCC's __USER_LABEL_PREFIX__ here, because
                     18:   dnl 1. It works only for GCC.
                     19:   dnl 2. It is incorrectly defined on some platforms, in some GCC versions.
                     20:   AC_CACHE_CHECK(
                     21:     [whether C symbols are prefixed with underscore at the linker level],
                     22:     [gl_cv_prog_as_underscore],
                     23:     [cat > conftest.c <<EOF
                     24: #ifdef __cplusplus
                     25: extern "C" int foo (void);
                     26: #endif
                     27: int foo(void) { return 0; }
                     28: EOF
                     29:      # Look for the assembly language name in the .s file.
                     30:      AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS -S conftest.c) >/dev/null 2>&1
                     31:      if grep _foo conftest.s >/dev/null ; then
                     32:        gl_cv_prog_as_underscore=yes
                     33:      else
                     34:        gl_cv_prog_as_underscore=no
                     35:      fi
                     36:      rm -f conftest*
                     37:     ])
                     38:   if test $gl_cv_prog_as_underscore = yes; then
                     39:     USER_LABEL_PREFIX=_
                     40:   else
                     41:     USER_LABEL_PREFIX=
                     42:   fi
                     43:   AC_DEFINE_UNQUOTED([USER_LABEL_PREFIX], [$USER_LABEL_PREFIX],
                     44:     [Define to the prefix of C symbols at the assembler and linker level,
                     45:      either an underscore or empty.])
                     46:   ASM_SYMBOL_PREFIX='"'${USER_LABEL_PREFIX}'"'
                     47:   AC_SUBST([ASM_SYMBOL_PREFIX])
                     48: ])