Conference turris::decc

    +---------------------------+ TM
    |   |   |   |   |   |   |   |
    | d | i | g | i | t | a | l |       Interoffice Memorandum
    |   |   |   |   |   |   |   |
    +---------------------------+


    To:  List                 Date:     11-FEB-1997
                              From:     The DEC C team
                              Group:    The Languages Group

    Subject: DEC C for OpenVMS Alpha compiler release


The DEC C development group announces the  availability of the ECO
kit V5.5-003 of DEC C for OpenVMS Alpha. This is a 32 bit native compiler
using a GEM BL32 backend.

The purpose of this kit is to provide a fix for the following two problems
found in DEC C V5.5-002

    o  A program that #includes the starlet header file <exc_handling.h>
       and is compiled with the /debug=symbols command qualifier
       causes the compiler to run indefinitely consuming more and
       more memory until some sort of system failure occurs. Depending
       on quotas and page file sizes, different symptoms ranging from
       tracebacks to system hangs can occur.

       The underlying cause of this failure is an infinite recursion
       when the compiler attempts to generate debug symbol table in-
       formation describing a struct or union type which contains a
       member that is a pointer to a qualified version of the con-
       taining struct or union type. The exc_handling.h header file
       contains such a type declaration. A simple example of such a
       declaration is:

              struct x {
                  volatile struct x *ptr;
              };

       Either the "const" or "volatile" type qualifiers in such a con-
       text will trigger the failure (the "__unaligned" type qualifier
       will not). The only workarounds are to compile without debug
       symbols or to modify the source code not to use these type
       qualifiers in such a context.

       This problem was introduced in V5.5-002 and is not present in
       earlier versions of the compiler.

    o  A compilation that requests a listing file (/list) and speci-
       fies more than one source file using a comma-separated list may
       fail with an ACCVIO or may simply omit a section of the listing
       for the second and subsequent source files.

       In V5.5-002, a new section was added to the end of the listing
       file to show the values of all predefined macros at compilation
       startup. This section should appear at the end of each separate
       listing file corresponding to each compilation for a comma-
       separated list. Within the compiler, the memory management
       cleanup between separate compilations for a comma-separated
       list corrupted the data used to produce this new section of
       listing. The usual effect is just to omit the new section in
       all but the first compilation, but it is possible for the com-
       piler to access violate. The workarounds are either to compile
       /nolist or to perform the compilations one at a time instead of
       using a comma list.

Network kits are contained in one save set at:

    DECC::DECC$KIT:[ALPHA]CC01055.A

This native kit is a regular VMSINSTAL kit, which requires an LMF  pak
and OpenVMS V6.1 (or higher).

    +---------------------------+ TM
    |   |   |   |   |   |   |   |
    | d | i | g | i | t | a | l |       Interoffice Memorandum
    |   |   |   |   |   |   |   |
    +---------------------------+


    To:  List                 Date:     20-MAR-1997
                              From:     The DEC C team
                              Group:    The Languages Group

    Subject: DEC C for OpenVMS Alpha compiler release


The DEC C development group announces the  availability of the field test
kit T5.6-001 of DEC C for OpenVMS Alpha.  This is a 32 bit native compiler
using a GEM BL33 backend.

This is primarily a maintenance release focused on bug fixes, performance,
usability and message improvements, and providing V7.1 runtime library features
on prior versions of VMS.  Enhancements include

o  Optimizer for Alpha now exploits the __restrict
   qualifier in limited ways. Future releases will expand
   this kind of optimization.

o  Optional compile-time diagnostics and optimizations for
   certain kinds of format strings passed to the printf
   family of library functions.

   If a preprocessor macro named "_INTRINSICS" is defined
   prior to inclusion of the V5.6 header file stdio.h, the
   compiler will perform compile-time analysis of format
   strings and arguments passed to printf, fprintf, and
   sprintf when possible. When the format string passed to
   one of these functions is an explicit compile-time-
   known string, this feature permits the compiler to
   diagnose mismatches in number and type between the %-
   specifiers in the format string and the arguments to be
   formatted. Most such format strings will be converted
   to a more efficient run-time encoding handled by new
   library routines. In addition, a number of special cases
   are recognized which will cause the compiler either to
   generate calls directly to lower-level library routines
   instead of printf, or to generate inline code, avoiding
   the need to do any format decoding at runtime. For
   example, a format such as "%s" passed to fprintf()
   can be converted to a call to fputs(). When passed
   to sprintf, it might be converted either to a call to
   strcpy or to inline code to copy characters into the
   buffer. In versions of OpenVMS through V7.1, the runtime
   support for this feature is provided only through object
   modules placed in SYS$LIBRARY:STARLET.OLB by this kit.


o  Message group C_TO_CXX. This message group contains an
   optional set of diagnostics that report the use of a
   number of C language constructs that are not compatible
   with, or have a slightly different meaning in, the C++
   language. This group may be enabled explicitly either on
   the command line (/WARN=ENABLE=C_TO_CXX) or by #pragma
   message enable (c_to_cxx).


o  New runtime check, /CHECK=POINTER_SIZE=INTEGER_CAST.
   This causes the compiler to generate code to check
   at runtime that casts from 64-bit pointer to 32-bit
   integer do not overflow. The expected behavior of casts
   to integer types is to truncate the value silently. But
   in porting 32-bit code to exploit 64-bit pointers, such
   casts can occur unintentionally and produce runtime
   failures that are otherwise very difficult to analyze.


o  New diagnostics to detect simple expressions with side
   effects that are undefined in ANSI C. The C standard
   formalized defacto rules about side effects in terms of
   sequence points. An expression that modifies the same
   object more than once, or that modifies an object and
   fetches its value for a purpose other than computing the
   modified value, has undefined behavior unless there is
   an intervening sequence point. The compiler now warns
   about such expressions (only for objects that are simple
   declared variables).


o  Source listings now include statement level nesting.
   The annotation at the left margin of the source listing
   now includes the statement nesting level in effect at
   the end of that source line. The statement nesting level
   appears as a simple integer before the listing line
   number. The block of a function definition is level 1.
   Outside of function definitions, this field is blank.


Network kits are contained in one save set at:

DECC::DECC$KIT:[ALPHA]CC056.A

For users who need compilers as old as V4.1 compiler which FRSed Nov '94,
savesets are available in the same directory:

DECC::DECC$KIT:[ALPHA]ALPHA_CC041.A,ALPHA_CC041.B
DECC::DECC$KIT:[ALPHA]CC050.A
DECC::DECC$KIT:[ALPHA]CC052.A
DECC::DECC$KIT:[ALPHA]CC053.A
DECC::DECC$KIT:[ALPHA]CC055.A

This native kit is a regular VMSINSTAL kit, which requires an LMF  pak
and OpenVMS V6.1 (or higher).

    +---------------------------+ TM
    |   |   |   |   |   |   |   |
    | d | i | g | i | t | a | l |       Interoffice Memorandum
    |   |   |   |   |   |   |   |
    +---------------------------+


    To:  List                 Date:     17-APR-1997
                              From:     The DEC C team
                              Group:    The Languages Group

    Subject: DEC C for OpenVMS Alpha compiler release


The DEC C development group announces the  availability of the sanity
kit T5.6-002 of DEC C for OpenVMS Alpha.  This is a 32 bit native compiler
using a GEM BL33 backend.

This is primarily a maintenance release focused on bug fixes, performance,
usability and message improvements, and providing V7.1 runtime library features
on prior versions of VMS.  Enhancements include

o  Optimizer for Alpha now exploits the __restrict
   qualifier in limited ways. Future releases will expand
   this kind of optimization.

o  Optional compile-time diagnostics and optimizations for
   certain kinds of format strings passed to the printf
   family of library functions.

   If a preprocessor macro named "_INTRINSICS" is defined
   prior to inclusion of the V5.6 header file stdio.h, the
   compiler will perform compile-time analysis of format
   strings and arguments passed to printf, fprintf, and
   sprintf when possible. When the format string passed to
   one of these functions is an explicit compile-time-
   known string, this feature permits the compiler to
   diagnose mismatches in number and type between the %-
   specifiers in the format string and the arguments to be
   formatted. Most such format strings will be converted
   to a more efficient run-time encoding handled by new
   library routines. In addition, a number of special cases
   are recognized which will cause the compiler either to
   generate calls directly to lower-level library routines
   instead of printf, or to generate inline code, avoiding
   the need to do any format decoding at runtime. For
   example, a format such as "%s" passed to fprintf()
   can be converted to a call to fputs(). When passed
   to sprintf, it might be converted either to a call to
   strcpy or to inline code to copy characters into the
   buffer. In versions of OpenVMS through V7.1, the runtime
   support for this feature is provided only through object
   modules placed in SYS$LIBRARY:STARLET.OLB by this kit.


o  Message group C_TO_CXX. This message group contains an
   optional set of diagnostics that report the use of a
   number of C language constructs that are not compatible
   with, or have a slightly different meaning in, the C++
   language. This group may be enabled explicitly either on
   the command line (/WARN=ENABLE=C_TO_CXX) or by #pragma
   message enable (c_to_cxx).


o  New runtime check, /CHECK=POINTER_SIZE=INTEGER_CAST.
   This causes the compiler to generate code to check
   at runtime that casts from 64-bit pointer to 32-bit
   integer do not overflow. The expected behavior of casts
   to integer types is to truncate the value silently. But
   in porting 32-bit code to exploit 64-bit pointers, such
   casts can occur unintentionally and produce runtime
   failures that are otherwise very difficult to analyze.


o  New diagnostics to detect simple expressions with side
   effects that are undefined in ANSI C. The C standard
   formalized defacto rules about side effects in terms of
   sequence points. An expression that modifies the same
   object more than once, or that modifies an object and
   fetches its value for a purpose other than computing the
   modified value, has undefined behavior unless there is
   an intervening sequence point. The compiler now warns
   about such expressions (only for objects that are simple
   declared variables).


o  Source listings now include statement level nesting.
   The annotation at the left margin of the source listing
   now includes the statement nesting level in effect at
   the end of that source line. The statement nesting level
   appears as a simple integer before the listing line
   number. The block of a function definition is level 1.
   Outside of function definitions, this field is blank.


Network kits are contained in one save set at:

DECC::DECC$KIT:[ALPHA]CC056.A

For users who need compilers as old as V4.1 compiler which FRSed Nov '94,
savesets are available in the same directory:

DECC::DECC$KIT:[ALPHA]ALPHA_CC041.A,ALPHA_CC041.B
DECC::DECC$KIT:[ALPHA]CC050.A
DECC::DECC$KIT:[ALPHA]CC052.A
DECC::DECC$KIT:[ALPHA]CC053.A
DECC::DECC$KIT:[ALPHA]CC055.A

This native kit is a regular VMSINSTAL kit, which requires an LMF  pak
and OpenVMS V6.1 (or higher).

    +---------------------------+ TM
    |   |   |   |   |   |   |   |
    | d | i | g | i | t | a | l |       Interoffice Memorandum
    |   |   |   |   |   |   |   |
    +---------------------------+


    To:  List                 Date:     23-APR-1997
                              From:     The DEC C team
                              Group:    The Languages Group

    Subject: DEC C for OpenVMS Alpha compiler release


The DEC C development group announces the  availability of the final SSB
kit V5.6-003 of DEC C for OpenVMS Alpha.  This is a 32 bit native compiler
using a GEM BL33 backend.

This is primarily a maintenance release focused on bug fixes, performance,
usability and message improvements, and providing V7.1 runtime library features
on prior versions of VMS.  Enhancements include

o  Optimizer for Alpha now exploits the __restrict
   qualifier in limited ways. Future releases will expand
   this kind of optimization.

o  Optional compile-time diagnostics and optimizations for
   certain kinds of format strings passed to the printf
   family of library functions.

   If a preprocessor macro named "_INTRINSICS" is defined
   prior to inclusion of the V5.6 header file stdio.h, the
   compiler will perform compile-time analysis of format
   strings and arguments passed to printf, fprintf, and
   sprintf when possible. When the format string passed to
   one of these functions is an explicit compile-time-
   known string, this feature permits the compiler to
   diagnose mismatches in number and type between the %-
   specifiers in the format string and the arguments to be
   formatted. Most such format strings will be converted
   to a more efficient run-time encoding handled by new
   library routines. In addition, a number of special cases
   are recognized which will cause the compiler either to
   generate calls directly to lower-level library routines
   instead of printf, or to generate inline code, avoiding
   the need to do any format decoding at runtime. For
   example, a format such as "%s" passed to fprintf()
   can be converted to a call to fputs(). When passed
   to sprintf, it might be converted either to a call to
   strcpy or to inline code to copy characters into the
   buffer. In versions of OpenVMS through V7.1, the runtime
   support for this feature is provided only through object
   modules placed in SYS$LIBRARY:STARLET.OLB by this kit.


o  Message group C_TO_CXX. This message group contains an
   optional set of diagnostics that report the use of a
   number of C language constructs that are not compatible
   with, or have a slightly different meaning in, the C++
   language. This group may be enabled explicitly either on
   the command line (/WARN=ENABLE=C_TO_CXX) or by #pragma
   message enable (c_to_cxx).


o  New runtime check, /CHECK=POINTER_SIZE=INTEGER_CAST.
   This causes the compiler to generate code to check
   at runtime that casts from 64-bit pointer to 32-bit
   integer do not overflow. The expected behavior of casts
   to integer types is to truncate the value silently. But
   in porting 32-bit code to exploit 64-bit pointers, such
   casts can occur unintentionally and produce runtime
   failures that are otherwise very difficult to analyze.


o  New diagnostics to detect simple expressions with side
   effects that are undefined in ANSI C. The C standard
   formalized defacto rules about side effects in terms of
   sequence points. An expression that modifies the same
   object more than once, or that modifies an object and
   fetches its value for a purpose other than computing the
   modified value, has undefined behavior unless there is
   an intervening sequence point. The compiler now warns
   about such expressions (only for objects that are simple
   declared variables).


o  Source listings now include statement level nesting.
   The annotation at the left margin of the source listing
   now includes the statement nesting level in effect at
   the end of that source line. The statement nesting level
   appears as a simple integer before the listing line
   number. The block of a function definition is level 1.
   Outside of function definitions, this field is blank.


Network kits are contained in one save set at:

DECC::DECC$KIT:[ALPHA]CC056.A

For users who need compilers as old as V4.1 compiler which FRSed Nov '94,
savesets are available in the same directory:

DECC::DECC$KIT:[ALPHA]ALPHA_CC041.A,ALPHA_CC041.B
DECC::DECC$KIT:[ALPHA]CC050.A
DECC::DECC$KIT:[ALPHA]CC052.A
DECC::DECC$KIT:[ALPHA]CC053.A
DECC::DECC$KIT:[ALPHA]CC055.A

This native kit is a regular VMSINSTAL kit, which requires an LMF  pak
and OpenVMS V6.1 (or higher).