Internal error during optimization for OpDecorateString with multiple literals

[theagentd]

The following GLSL fragment shader fails to compile to SPIR-V when optimizations are turned on:

#extension GL_EXT_spirv_intrinsics : require

spirv_decorate_string(5635, "string1", "string2") layout(location = 0) out float test;

void main() {
    test = 0.0;
}

It seems that the optimizer does not handle OpDecorateString opcodes that have multiple string literals correctly.

shaderc: internal error: compilation succeeded but failed to optimize: Invalid instruction OpDecorateString starting at word 184: expected no more operands after 5 words, but stated word count is 7.

Without optimizations, the shader compiles correctly, and both the "string1" and "string2" literals are correctly included in the resulting OpDecorateString, so clearly the error is invalid; the OpDecorateString instruction IS valid and correct.