Cannot initialize a struct with a previously declared const struct.

[negge]

Initializing a struct is valid C99 but does not work with WATCOM. For example,

typedef struct Point2D Point2D;

struct Point2D {
  float x;
  float y;
};

const Point2D ZERO = { 0, 0 };

Point2D pos = ZERO;

void main() {
  pos.x += 1;
}

This builds fine with gcc and clang, but building with wcc I get the following errors:

$ wcc test.c
Open Watcom C x86 16-bit Optimizing Compiler
Version 2.0 beta Jun  1 2024 01:58:31 (32-bit)
Copyright (c) 2002-2024 The Open Watcom Contributors. All Rights Reserved.
Portions Copyright (c) 1984-2002 Sybase, Inc. All Rights Reserved.
Source code is available under the Sybase Open Watcom Public License.
See https://github.com/open-watcom/open-watcom-v2#readme for details.
test.c(10): Error! E1070: Data for aggregate type must be enclosed in curly braces
test.c(10): Error! E1054: Expression must be constant
test.c(10): Error! E1009: Expecting ',' but found ';'
test.c(12): Error! E1063: Missing operand
test.c(12): Error! E1054: Expression must be constant
test.c(12): Error! E1009: Expecting ';' but found 'void'
test.c: 15 lines, 0 warnings, 6 errors

This has many peculiar error messages. E1054 is odd because the expression on line 10 is constant but I think that is a result of E1070 happening first.

[jmalak]

You are in C89 mode.

[negge]

Are you sure that is it? Setting C99 mode gives the same errors:

$ wcc -zastd=c99 test.c
Open Watcom C x86 16-bit Optimizing Compiler
Version 2.0 beta Jun  1 2024 01:58:31 (32-bit)
Copyright (c) 2002-2024 The Open Watcom Contributors. All Rights Reserved.
Portions Copyright (c) 1984-2002 Sybase, Inc. All Rights Reserved.
Source code is available under the Sybase Open Watcom Public License.
See https://github.com/open-watcom/open-watcom-v2#readme for details.
test.c(10): Error! E1070: Data for aggregate type must be enclosed in curly braces
test.c(10): Error! E1054: Expression must be constant
test.c(10): Error! E1009: Expecting ',' but found ';'
test.c(12): Error! E1063: Missing operand
test.c(12): Error! E1054: Expression must be constant
test.c(12): Error! E1009: Expecting ';' but found 'void'
test.c: 15 lines, 0 warnings, 6 errors