Brace-enclosed initializing of a union type

[madebr]

While trying to build dethrace with OpenWatcom 2 (I haven't tried 1.x), I stumbled on this issue.
Dethrace is a CMake project, to which I had to apply small patches to support OpenWatcom.

Brace-enclosed initializing of a union type does not seem to work.

Building the example below in a minimal CMake project causes the following errors to be emitted:

Error log

/home/maarten/owatcom2/binl/wcl386 -zq -d+  -I/home/maarten/owatcom2/h -I/home/maarten/owatcom2/h/nt -aa -za -s -ot -d0 -dNDEBUG -foCMakeFiles/union_test.dir/main.c.obj -c -cc /home/maarten/projects/issues/main.c
/home/maarten/projects/issues/main.c(45): Error! E1063: Missing operand
/home/maarten/projects/issues/main.c(45): Error! E1009: Expecting ',' but found '{'
/home/maarten/projects/issues/main.c(45): Error! E1009: Expecting '}' but found '.'
/home/maarten/projects/issues/main.c(45): Error! E1009: Expecting ',' but found 'i'
/home/maarten/projects/issues/main.c(45): Error! E1063: Missing operand
/home/maarten/projects/issues/main.c(45): Error! E1009: Expecting ';' but found '}'
/home/maarten/projects/issues/main.c(45): Warning! W107: Missing return value for function 'main'
/home/maarten/projects/issues/main.c(45): Error! E1061: Expecting data or function declaration, but found ','
/home/maarten/projects/issues/main.c(46): Error! E1026: Invalid declarator
/home/maarten/projects/issues/main.c(46): Error! E1009: Expecting ';' but found '{'
/home/maarten/projects/issues/main.c(46): Error! E1061: Expecting data or function declaration, but found '{'
/home/maarten/projects/issues/main.c(46): Warning! W132: No storage class or type specified
/home/maarten/projects/issues/main.c(46): Error! E1034: Symbol 'BRT_MATRIX4' already defined
/home/maarten/projects/issues/main.c(46): Note! N2002: 'BRT_MATRIX4' defined in: /home/maarten/projects/issues/main.c(11)
/home/maarten/projects/issues/main.c(46): Error! E1034: Symbol 'br_value' already defined
/home/maarten/projects/issues/main.c(46): Note! N2002: 'br_value' defined in: /home/maarten/projects/issues/main.c(35)
/home/maarten/projects/issues/main.c(46): Error! E1129: Type does not agree with previous definition of 'br_value'
/home/maarten/projects/issues/main.c(46): Note! N2002: 'br_value' defined in: /home/maarten/projects/issues/main.c(35)
/home/maarten/projects/issues/main.c(46): Error! E1009: Expecting ';' but found '{'
/home/maarten/projects/issues/main.c(46): Error! E1061: Expecting data or function declaration, but found '{'
/home/maarten/projects/issues/main.c(46): Error! E1026: Invalid declarator
/home/maarten/projects/issues/main.c(46): Error! E1009: Expecting ';' but found '.'
/home/maarten/projects/issues/main.c(46): Error! E1061: Expecting data or function declaration, but found '.'
/home/maarten/projects/issues/main.c(46): Warning! W132: No storage class or type specified
/home/maarten/projects/issues/main.c(46): Warning! W102: Type mismatch (warning)
/home/maarten/projects/issues/main.c(46): Note! N2003: source conversion type is 'int *'
/home/maarten/projects/issues/main.c(46): Note! N2004: target conversion type is 'int'
/home/maarten/projects/issues/main.c(46): Error! E1009: Expecting ';' but found '}'
/home/maarten/projects/issues/main.c(46): Error! E1061: Expecting data or function declaration, but found '}'
/home/maarten/projects/issues/main.c(46): Error! E1147: Too many errors: compilation aborted
Error: Compiler returned a bad status compiling '/home/maarten/projects/issues/main.c'
ninja: build stopped: subcommand failed.

Small example

# Save this file as CMakeLists.txt
cmake_minimum_required(VERSION 3.20)
project(openwatcom_unions)
add_executable(union_test main.c)

/* Save this file as main.c */
#include <stddef.h>

typedef enum {
    BRT_NULL_TOKEN,
    BRT_TOKEN,
    BRT_NULL,
    BRT_POINTER,
    BRT_FLOAT,
    BRT_INTEGER,
    BRT_MATRIX3,
    BRT_MATRIX4,
    BRT_MATRIX34
} br_token;

typedef struct {
    float v[4][4];
} matrix4_t;

typedef struct {
    float v[4][3];
} matrix34_t;

typedef struct {
    float v[3][3];
} matrix3_t;

typedef union {
    void *p;
    float f;
    int i;
    br_token t;
    matrix3_t *m3;
    matrix4_t *m4;
    matrix34_t *m34;
} br_value;

typedef struct {
    br_token a;
    br_value v;
} br_token_value;

int main(int argc, char *argv[]) {
    matrix4_t m4;
    br_token_value is_alternative[] = {
        { BRT_INTEGER, (br_value) { .i = 1337 } },
        { BRT_MATRIX4 , (br_value) { .m4 = &m4 }},
        { BRT_NULL_TOKEN , (br_value) { .p = NULL }}
    };
    return 0;
}

I can also reproduce this on ci: this is the project, and this is the ci result

edit
I've been asked to run wcl386 without -zq so it showed the wcc386 invocation.
The build system runs (after configuring with -DCMAKE_C_FLAGS="-aa -za99"):

/home/maarten/owatcom2/binl/wcl386 -zq -d+  -I/home/maarten/owatcom2/h -I/home/maarten/owatcom2/h/nt -aa -za99 -s -ot -d0 -dNDEBUG -foCMakeFiles/union_test.dir/src.c.obj -c -cc /home/maarten/projects/issues/src.c

Removing -zq shows:

wcc386 /home/maarten/projects/issues/src.c  -d+ -I/home/maarten/owatcom2/h -I/home/maarten/owatcom2/h/nt -aa -za99 -s -ot -d0 -dNDEBUG -foCMakeFiles/union_test.dir/src.c.obj

[jmalak]

Thanks for your bug report.